100525 + Interview Questions in GENERAL QA IN GENERAL AWARENESS

1.	Avinash, Manoj and Arun started a business in partnership investing in the ratio of 3:2:5 respectively. At the end of the year they earned a profit of Rs 45,000 which is 15% of their total investment. How much did Manoj invest?(a) Rs.60,000 (b) Rs.1,80,00 (c) Rs. 30,000 (d) Rs.90,000 (e) None of these
Answer» (a) Total investment =100/15x45000 =Rs.300000 Avinash : Manoj : Arun = 3 : 2 : 5 Investment of Manoj =(2/10x300000) = Rs.60000

Discussion

2.	Read the hypothetical text and answer the following questions.Arun, Varun and Tarun were partners in a firm sharing profits equally. On 1st April, 2020, their capitals stood at ₹ 2, 00,000, ₹ 1, 50,000 and ₹ 1, 00,000 respectively. As per the provisions of Partnership Deed:1) Arun was entitled to a salary of ₹ 2,500 p.m.2) Partners were entitled to interest on capital @ 10% p.a.The net profit for the year ended 31st March, 2021, ₹ 1,50,000 was distributed among the partners without providing for the above items.Q1.What is the amount of interest on capital of Varun?a) ₹ 20,000b) ₹ 15,000 c) ₹ 10,000 d) ₹ 30,000 Q2. What is the amount of distributable profit for the partners after providing salary and interest on capitals to the partners? a) ₹ 50,000 each b) ₹ 25,000 each c) ₹ 10,000 each d) ₹ 15,000 each Q3. Arun’s Capital A/c will be credited with Rs…………….for giving the adjustment to above omissions. a) ₹ 20,000 b) ₹ 15,000 c) ₹ 25,000 d) ₹ 10,000 Q4. Capital Account/Accounts of …………………… will be debited to give the effect of above adjustments. a) Varun b) Tarun and Arun c) Arun and Varun d) Varun and Tarun
Answer» Correct option is 1 a) ₹ 20,000 2 b) ₹ 25,000 each 3 c) ₹ 25,000 4 d) Varun and Tarun

2.

Read the hypothetical text and answer the following questions.Arun, Varun and Tarun were partners in a firm sharing profits equally. On 1st April, 2020, their capitals stood at ₹ 2, 00,000, ₹ 1, 50,000 and ₹ 1, 00,000 respectively. As per the provisions of Partnership Deed:1) Arun was entitled to a salary of ₹ 2,500 p.m.2) Partners were entitled to interest on capital @ 10% p.a.The net profit for the year ended 31st March, 2021, ₹ 1,50,000 was distributed among the partners without providing for the above items.Q1.What is the amount of interest on capital of Varun?a) ₹ 20,000b) ₹ 15,000 c) ₹ 10,000 d) ₹ 30,000 Q2. What is the amount of distributable profit for the partners after providing salary and interest on capitals to the partners? a) ₹ 50,000 each b) ₹ 25,000 each c) ₹ 10,000 each d) ₹ 15,000 each Q3. Arun’s Capital A/c will be credited with Rs…………….for giving the adjustment to above omissions. a) ₹ 20,000 b) ₹ 15,000 c) ₹ 25,000 d) ₹ 10,000 Q4. Capital Account/Accounts of …………………… will be debited to give the effect of above adjustments. a) Varun b) Tarun and Arun c) Arun and Varun d) Varun and Tarun

Answer»

Correct option is

1 a) ₹ 20,000

2 b) ₹ 25,000 each

3 c) ₹ 25,000

4 d) Varun and Tarun

Discussion

3.	If the distance between the points (2, 3) and (a, 0) is 3 then a = ______(A) 2 (B) 3 (C) 5 (D) 1
Answer» Correct option (A) 2 Explanation: (2, 3) and (a, 0) distance = 3 Distance = d² = (x₂ – x₁)² + (y₂ – y₁)² 3² = (a – 2)² +(0 – 3)² 0 = (a – 2)² ∴ a – 2 = 0 ⇒ a = 2

3.

If the distance between the points (2, 3) and (a, 0) is 3 then a = ______(A) 2 (B) 3 (C) 5 (D) 1

Answer»

Correct option (A) 2

Explanation:

(2, 3) and (a, 0) distance = 3

Distance = d² = (x₂ – x₁)² + (y₂ – y₁)²

3² = (a – 2)² +(0 – 3)²

0 = (a – 2)²

∴ a – 2 = 0

⇒ a = 2

Discussion

4.	If total number of observations are even, then the median of these observations is equal to ______.1. \({1\over4}[{n\over4}^{th} term \space + {({n\over4} + 1})^{th} term]\)2. \({1\over2}[{n\over2}^{th} term \space + {({n\over2} + 1})^{th} term]\)3. \({3\over2}[{n\over2}^{th} term \space + {({n\over2} + 1})^{th} term]\)4. \({1\over2}[{n\over2}^{th} term \space + {({n\over3} + 1})^{th} term]\)
Answer» Correct Answer - Option 2 : \({1\over2}[{n\over2}^{th} term \space + {({n\over2} + 1})^{th} term]\) Formula used: If the total number of observation given is odd, then the formula to calculate the median is: Median = {(n+1)/2}^th term If the total number of observation is even, then the median formula is: Median = [(n/2)^th term + {(n/2)+1}^thterm]/2 where n is the number of observations Note:- In the official question option 1 is marked as correct but correct answer is option 2

4.

If total number of observations are even, then the median of these observations is equal to ______.1. \({1\over4}[{n\over4}^{th} term \space + {({n\over4} + 1})^{th} term]\)2. \({1\over2}[{n\over2}^{th} term \space + {({n\over2} + 1})^{th} term]\)3. \({3\over2}[{n\over2}^{th} term \space + {({n\over2} + 1})^{th} term]\)4. \({1\over2}[{n\over2}^{th} term \space + {({n\over3} + 1})^{th} term]\)

Answer» Correct Answer - Option 2 : \({1\over2}[{n\over2}^{th} term \space + {({n\over2} + 1})^{th} term]\)

Formula used:

If the total number of observation given is odd, then the formula to calculate the median is:

Median = {(n+1)/2}^th term

If the total number of observation is even, then the median formula is:

Median = [(n/2)^th term + {(n/2)+1}^thterm]/2

where n is the number of observations

Note:- In the official question option 1 is marked as correct but correct answer is option 2

Discussion

5.	The median of a set of `9` distinct observations is `20.5`. If each of the largest `4` observations of the set is increased by `2`, then the median of the new setA. is incrased by `2`B. is decreased by `2`C. is two times the original medianD. remains the same as that of the original set
Answer» Correct Answer - D Median of new set remains the same as that of the original set.

Discussion

6.	If `A(1,p^(2)),B(0,1)` and `C(p,0)` are the coordinates of three points then area of the triangle `ABC` is `1/(lamda)\|p^(3)-p+1\|`. The value of `lamda` is
Answer» Correct Answer - 2 `A=1/2\|(1,p^(2),1),(0,1,1),(p,0,1)\|=1/2[1(1-0)+p(p^(2)-1)]=1/2(p^(3)-p+1)` Hence `A=1/2\|p^(3)-p+1\|`

Discussion

7.	If `A=[{:(1,-1,1),(0,2,-3),(2,1,0):}]` and `B=(adjA)` and `C=5A`, then find the value of `(\|adjB\|)/(\|C \|)`
Answer» Correct Answer - 1 `(\|adj(adjA)\|)/(\|5A\|)=(\|A\|^((3-1)^(2)))/(5^(3)\|A\|)=(5^(4))/(5^(3).5)=1`

Discussion

8.	If discriminant of f(x) = ax2 + bx + c is negative and a + b + c > 0 then find whether the Quadratic function is opening upward or opening downwards.
Answer» The graph of quadratic polynomial is opening upward if a > 0 and opening downward if a < 0.

Discussion

9.	The simplified value of cosθ secθ + sinθ cosθ is (A) 2 (B) 3 (C) 0 (D) 1
Answer» cosθ x secθ + sinθ x cosecθ is = 1 + 1 = 2

9.

The simplified value of cosθ secθ + sinθ cosθ is (A) 2 (B) 3 (C) 0 (D) 1

Answer»

cosθ x secθ + sinθ x cosecθ is

= 1 + 1 = 2

Discussion

10.	Find:The 10th term of the G.P. √2, \(\frac{1}{\sqrt{2}}, \frac{1}{2\sqrt{2}}\),........
Answer» T_n= ar^n-1 a = √2, r = \(\frac{\frac{1}{\sqrt{2}}}{\sqrt{2}}\) = \(\frac{1}{2}\) \(\therefore\) T₁₀ = √2\((\frac{1}{2})^{10-1}\) = \(\frac{\sqrt{2}}{512}\) = \(\frac{1}{256\sqrt{2}}\) \(\therefore\) The 10 terms is \(\frac{1}{256\sqrt{2}}\)

10.

Find:The 10th term of the G.P. √2, \(\frac{1}{\sqrt{2}}, \frac{1}{2\sqrt{2}}\),........

Answer»

T_n= ar^n-1

a = √2, r = \(\frac{\frac{1}{\sqrt{2}}}{\sqrt{2}}\) = \(\frac{1}{2}\)

\(\therefore\) T₁₀ = √2\((\frac{1}{2})^{10-1}\)

= \(\frac{\sqrt{2}}{512}\)

= \(\frac{1}{256\sqrt{2}}\)

\(\therefore\) The 10 terms is \(\frac{1}{256\sqrt{2}}\)

Discussion

11.	If sin cos⁻¹ (1 + x) = cos tan⁻¹ x then x is.
Answer» nai aata nai aata

Discussion

12.	If \( u=\log \left(x^{2}+y^{2}+z^{2}\right) \), then the value of \( x u_{x}+y u_{y}+z u_{z} \) is equal to
Answer» u = log(x² + y² + z²) ⇒ e^u = x² + y² + z² For \(u_x = \frac{\partial u}{\partial x}, e^u \frac{\partial u}{\partial x}= 2x\) \(\frac{\partial u}{\partial x} = \frac{2x}{e^u} = 2xe^{-u}\) Similarly \(\frac{\partial u}{\partial y} = 2ye^{-u}\) & \(\frac{\partial u}{\partial z} = 2ze^{-u}\) Now, xu_x + yu_y + zu_z = 2x²e^-u + 2y²e^-u + 2z²e^-4 = 2e^-u(x² + y² + z²) = 2e^-u e^u = 2

12.

If \( u=\log \left(x^{2}+y^{2}+z^{2}\right) \), then the value of \( x u_{x}+y u_{y}+z u_{z} \) is equal to

Answer»

u = log(x² + y² + z²)

⇒ e^u = x² + y² + z²

For \(u_x = \frac{\partial u}{\partial x}, e^u \frac{\partial u}{\partial x}= 2x\)

\(\frac{\partial u}{\partial x} = \frac{2x}{e^u} = 2xe^{-u}\)

Similarly \(\frac{\partial u}{\partial y} = 2ye^{-u}\) & \(\frac{\partial u}{\partial z} = 2ze^{-u}\)

Now,

xu_x + yu_y + zu_z = 2x²e^-u + 2y²e^-u + 2z²e^-4

= 2e^-u(x² + y² + z²)

= 2e^-u e^u

= 2

Discussion

13.	What _____ the weather _____ in Las Vegas the day before yesterday. A) were / like B) was/as C) is / like D) was/like
Answer» Correct option is D) was/like

Discussion

14.	“Monoculture of commercially viable trees is destroying the unique natural profile. Thoughtless exploitation of timber, deforesting vast tracts for palm cultivation, destruction of mangroves, illegal logging by tribals and poaching only compounds the problem. Fresh water pockets are fast drying up due to deforestation and destruction of mangroves”. The place referred to this quotation is : (a) Sundarban (b) Kerala coast (c) Orissa coast (d) Andaman and Nicobar Island
Answer» (a) The quotation referred to Sundarban of West Bengal. Sundarban is famous for mangrove forest and tiger population. It is present at the delta region of Ganga. Sundarban is world’s largest delta.

Discussion

15.	Famous 'Kamakhya Devi Temple' is located in which state?1. Assam2. Madhya Pradesh3. Himachal Pradesh4. Karnataka
Answer» Correct Answer - Option 1 : Assam The Kamakhya Devi Temple is located at Guhawati, Assam. The famous Ambubachi Mela is held here every year. The Temple is Situated in Nilachal Hills in Guwahati, Assam. It is one of the 52 Shakti Peeths. Kamakhya Devi is also Known as the Goddess of Fertility.

Discussion

16.	The coefficient of linear expansion varies linearly from `alpha_(1)` to `alpha_(2)` in a rod of length l. Find the increase in length when the temperature is increased by `DeltaT`.A. `((alpha_(1)+alpha_(2))/(2))lDeltaT`B. `(alpha_(1)+alpha_(2))lDeltaT`C. `(alpha_(1)+(alpha_(2))/(2))lDeltaT`D. `((alpha_(1))/(2)+alpha_(2))lDeltaT`
Answer» Correct Answer - A Time lost or time gained by pendulum clock per second is given by `Deltat=(1)/(2)alphaDeltaT` implies time lost or gained per day is `Deltat=((1)/(2)alphaDeltaT)xx86400` If graduation temperature of clock is `T_(0)` at `15^(@)C`, clock is gaining 5 sec. `implies 5=(1)/(2)alpha(T_(0)-15)xx86400implies2(T_(0)-15)=(30-T_(0))implies T_(0)=20^(@)C` `5=(1)/(2)alpha(20-15)86400` `alpha=(2)/(86400)implies alpha=2.3 xx10^(-5)//.^(@)C`

Discussion

17.	If the sequence of the coding strand in a transcription unit is written asfollows:5'-ATGCATGCATGCATGCATGCATGCATGC-3'. Write down thesequence of mRNA.
Answer» If the coding strand in a transcription unit is 5’− ATGCATGCATGCATGCATGCATGCATGC-3’ Then, it is known that the sequence of mRNA is same as the coding strand of DNA. However, in RNA, thymine is replaced by uracil. Hence, the sequence of mRNA will be 5’ − AUGCAUGCAUGCAUGCAUGCAUGCAUGC-3’

17.

If the sequence of the coding strand in a transcription unit is written asfollows:5'-ATGCATGCATGCATGCATGCATGCATGC-3'. Write down thesequence of mRNA.

Answer»

If the coding strand in a transcription unit is

5’− ATGCATGCATGCATGCATGCATGCATGC-3’

Then, it is known that the sequence of mRNA is same as the coding strand of DNA.

However, in RNA, thymine is replaced by uracil.

Hence, the sequence of mRNA will be

5’ − AUGCAUGCAUGCAUGCAUGCAUGCAUGC-3’

Discussion

18.	Which of the following is correct order for basic nature?A. `CH_(3)FgtCH_(3)OHgtCH_(3)NH_(2)`B. `CH_(3)FgtCH_(3)NH_(2)gtCH_(3)OH`C. `CH_(3)NH_(2)gtCH_(3)FgtCH_(3)OH`D. `CH_(3)NH_(2)gtCH_(3)OHgtCH_(3)F`
Answer» `CH_(3)NH_(2)` is more basic due to pair on `N` and `+I.E` of `CH_(3)` group `CH_(3)OH` is acidic due to `O-H` group `CH_(3) F` is neutral.

Discussion

19.	What are the salient features of valence bond theroy (VBT) ?
Answer» The sailent feature of valence bond theory (VBT) are as follows: (1) Accoriding to this thory , a centreal metal atom or ion present in a complex provides a definite number of vannct orbitals (s,p , d and f) to commodate the electrons from the ligands for the formation coordinate bonds with the metal ion / atom. (2) The number of vacant orbitals provided by the central metal atom or ion is the same as the coordination number of the metal. For example: `Cu^(2+)` provides 4 vacant orbitals in the complex, `[Cu(NH_(3)_(4)]^(2+)`. (3) The vacant orbitals of metal atom or ion undergo hybridisation forming the same number of hybridised orbitals, since the bonding with the hybrid orbitals is stronger. (4) Each ligand has one or more orbitals containing one or more lone pairs of the electrons. (5) A coordinate bond is formed by the overlapping of the hybrid orbital of the metal atom or ion with the filled orbitals of the ligands with a lone pair of electrons. (6) Hence each coordinate bond provides two electroms to the central metal atom or ion. (7) Greater the overlapping, the stronger is the coordinate bonds. (8) When inner orbitals namely (n - 1) d-orbitals in transtition metal atom are ion hydridise , the complex is alled inner complex and when outer orbitals i.e., nd-orbitals hydridise then the complex is called outer complex. (9) When the central metal atom or ion in the complex contains one or more unpaired electrons the complex is paramagnetic while if all the electrons are paired, the complex is diamagnetic. (10) Strong field ligands like `NH_(3)`, `CN^(-)`, etc. in the complex cause pairing of the unpaired electrons present in the metal atom or ion. This process is called spin pairing process. This changes the magnetic properties of the complex.

Discussion

20.	Which set represents interamolecular redox changes? `1. 2KClO_(3)to 2KCl+3O_(2)` `2.(NH_(4))_(2)Cr_(2)O_(7)toN_(2)+Cr_(2)O_(3)+4H_(2)O` `3. Cl_(2)+OH^(-)toClO^(-)+Cl^(-)+H^(+)` `4. Mn_(2)O_(7)to2MnO_(2)+3//2O_(2)`A. `1,2,4`B. `1,2,3`C. `3,4`D. `2,3`
Answer» Rest all are intramolecular redox.

Discussion

21.	A heavy weight is suspended from a spring Te energy stored in the spring is E. If the weight is raised till the spring comes to its stretched position and the work done in doing so be W. then gain in gravitational potential energy of the weight will be : (A) W + E (B) W – E (C) W(D) E
Answer» Answer is (A) W + E Gain in gravitational potential energy = work done + energy lost by the spring.

21.

A heavy weight is suspended from a spring Te energy stored in the spring is E. If the weight is raised till the spring comes to its stretched position and the work done in doing so be W. then gain in gravitational potential energy of the weight will be : (A) W + E (B) W – E (C) W(D) E

Answer»

Answer is (A) W + E

Gain in gravitational potential energy = work done + energy lost by the spring.

Discussion

22.	A circular loop placed in a plane perpendicular to the plane of paper carries a current when the key is ON. The current as seen from points A and B (in the plane of paper and on the axis of the coil) is anti clockwise and clockwise respectively. The magnetic field lines point from B to A. The N-pole of the resultant magnet is on the face close to(a) A (b) B(c) A if the current is small, and B if the current is large(d) B if the current is small and A if the current is large
Answer» (a) Hint— Misconception is that magnetic field lines point from north to south pole. The fact is that they emerge out of North pole and entre into South pole.

Discussion

23.	(a) The direction of magnetic field at a point is taken to be the direction in which the north pole of a magnetic compass needle points(b) Magnetic field lines are closed curves(c) If magnetic field lines are parallel and equidistant, they represent zero field strength(d) Relative strength of magnetic field is shown by the degree of closeness of the field lines
Answer» (c) If magnetic field lines are parallel and equidistant, they represent zero field strength

Discussion

24.	National Highway 44 originates from which district of Rajasthan?1. Sawai Madhopur2. Dausa3. Dholpur4. Karauli
Answer» Correct Answer - Option 3 : Dholpur The correct answer is Dholpur. National Highway 44 originates from Dholpur district of Rajasthan. National Highway 44 (NH 44) is the longest-running major north-south National Highway in India. It passes through the Union Territory of Jammu and Kashmir, in addition to the states of Punjab, Haryana, Delhi, Uttar Pradesh, Rajasthan, Madhya Pradesh, Maharashtra, Telangana, Andhra Pradesh, Karnataka, and Tamil Nadu. Length 4,112 km. North end Srinagar, Jammu and Kashmir South end Kanyakumari, Tamil Nadu.

24.

National Highway 44 originates from which district of Rajasthan?1. Sawai Madhopur2. Dausa3. Dholpur4. Karauli

Answer» Correct Answer - Option 3 : Dholpur

The correct answer is Dholpur.

National Highway 44 originates from Dholpur district of Rajasthan.

National Highway 44 (NH 44) is the longest-running major north-south National Highway in India.
- It passes through the Union Territory of Jammu and Kashmir, in addition to the states of Punjab, Haryana, Delhi, Uttar Pradesh, Rajasthan, Madhya Pradesh, Maharashtra, Telangana, Andhra Pradesh, Karnataka, and Tamil Nadu.
- Length 4,112 km.
- North end Srinagar, Jammu and Kashmir
- South end Kanyakumari, Tamil Nadu.

Discussion

25.	factors influencing the heat developed when a current passes through a conductor.
Answer» Electric current Resistance of the conductor Time of current flow

Discussion

26.	Correct the mistakes, if any:a. Amperage decreases in proportion to the decrease in the area of cross-section of the conductor.b. Connecting appliances in a circuit beyond its power capacity is short circuit.c. It is to reduce the heat loss that electric lamps are filled with inert gases.
Answer» b. Overloading is connecting appliances with more power in the circuit, than it can bear. c. Inert gases are filled in filament lamps to reduce the rate of evaporation.

26.

Correct the mistakes, if any:a. Amperage decreases in proportion to the decrease in the area of cross-section of the conductor.b. Connecting appliances in a circuit beyond its power capacity is short circuit.c. It is to reduce the heat loss that electric lamps are filled with inert gases.

Answer»

b. Overloading is connecting appliances with more power in the circuit, than it can bear.

c. Inert gases are filled in filament lamps to reduce the rate of evaporation.

Discussion

27.

a. Complete the table based on the amperage of the fuse wire.Electric deviceOperatingvoltage (V)Power of thedevice (p)Current throughthe circuitI = P/VThe amperageof the fuse to beused in the circuit (A)Water heater230 V4370 W19 A.......Air conditioner (AC)230 V3335 W14.5 A......Television (LED-TV)230 V57.5 W0.25 A......Computer (Laptop)230 V28.75 W0.125 A......b. The amperage of the fuse wire used in a circuit that works on 230 V is 2.2 A. If so the power of the device isi. less than 300 Wii. 300 W to 500 Wiii. between 500 Wand 510 Wiv. more than 510 W

Answer»

a.

Electric device	Operating voltage (V)	Power of the device (p)	Current through the circuit I = P/V	The amperage of the fuse to be used in the circuit (A)
Water heater	230 V	4370 W	19 A	20 A
Air conditioner (AC)	230 V	3335 W	14.5 A	15 A
Television (LED-TV)	230 V	57.5 W	0.25 A	0.3 A
Computer (Laptop)	230 V	28.75 W	0.125 A	0.2 A

b.

iii. between 500 W and 510 W

Discussion

28.	Light of a certain wavelength has a wave number `barv` in vacum. Its wave number in a medium of refractive index n isA. `n/v`B. `(1)/(n barv)`C. `(barv)/(n)`D. `n barv`
Answer» Correct Answer - D `n barv` `bar(lamda_(a))=barv,barlamda_(m)= ?, mu =n` `m =(lamda_(a))/(lamda_(m))=(bar(lamda_(m)))/(lamda_(m))=(bar(lamda_(m)))/(barv)` `bar(lamda_(m)) =m barv` `= n barv. `

Discussion

29.	A concave mirror produces three times magnified real image of an object placed at 10 cm in front of it. Where is the image located?
Answer» We have, m = 3 u = -10cm ∴ m = \(\frac{-v}{u}\) or, 3 = \(\frac{(-v)}{(-10)}\) Or, ν = 30 cm Thus, the image is formed at distance of 30 cm behind the mirror. Or, ν = 30 cm Thus, the image is formed at distance of 30 cm behind the mirror. Given , m = +3 (As image is real ) u = -10 cm v = ? we know that , m = -v / u = 3 = -v / -10 ⇒ -v = -30 ⇒ v = 30 cm Hence the mirror is placed at 30 cm behind the mirror .

29.

A concave mirror produces three times magnified real image of an object placed at 10 cm in front of it. Where is the image located?

Answer»

We have, m = 3

u = -10cm

∴ m = \(\frac{-v}{u}\)

or, 3 = \(\frac{(-v)}{(-10)}\)

Or, ν = 30 cm

Thus, the image is formed at distance of 30 cm behind the mirror.

Or, ν = 30 cm

Thus, the image is formed at distance of 30 cm behind the mirror.

Given , m = +3 (As image is real )

u = -10 cm v = ?

we know that ,

m = -v / u = 3 = -v / -10

⇒ -v = -30 ⇒ v = 30 cm

Hence the mirror is placed at 30 cm behind the mirror .

Discussion

30.	(a) a concave mirror(b) a convex mirror(c) a plane mirror(d) both concave as well as plane mirror
Answer» (b) a convex mirror

Discussion

31.	Under which of the following conditions a concave mirror can form an image larger than the actual object?(a) When the object is kept at a distance equal to its radius of curvature(b) When object is kept at a distance less than its focal length(c) When object is placed between the focus and centre of curvature(d) When object is kept at a distance greater than its radius of curvature
Answer» (c) When object is placed between the focus and centre of curvature

Discussion

32.	A virtual image larger than the object can be obtained by(a) concave mirror (b) convex mirror(c) plane mirror (d) concave lens
Answer» (a) Virtual image formed is larger in size in case of concave mirror.

Discussion

33.	Answer the following questions: (a) You have learnt that plane and convex mirrors produce virtual images of objects. Can they produce real images under some circumstances? Explain. (b) A virtual image, we always say, cannot be caught on a screen. Yet when we ‘see’ a virtual image, we are obviously bringing it on to the ‘screen’ (i.e., the retina) of our eye. Is there a contradiction?(c) A diver under water, looks obliquely at a fisherman standing on the bank of a lake. Would the fisherman look taller or shorter to the diver than what he actually is?(d) Does the apparent depth of a tank of water change if viewed obliquely? If so, does the apparent depth increase or decrease?(e) The refractive index of diamond is much greater than that of ordinary glass. Is this fact of some use to a diamond cutter?
Answer» (a) Yes Plane and convex mirrors can produce real images as well. If the object is virtual, i.e., if the light rays converging at a point behind a plane mirror (or a convex mirror) are reflected to a point on a screen placed in front of the mirror, then a real image will be formed. (b) No A virtual image is formed when light rays diverge. The convex lens of the eye causes these divergent rays to converge at the retina. In this case, the virtual image serves as an object for the lens to produce a real image. (c) The diver is in the water and the fisherman is on land (i.e., in air). Water is a denser medium than air. It is given that the diver is viewing the fisherman. This indicates that the light rays are travelling from a denser medium to a rarer medium. Hence, the refracted rays will move away from the normal. As a result, the fisherman will appear to be taller. (d) Yes; Decrease The apparent depth of a tank of water changes when viewed obliquely. This is because light bends on traveling from one medium to another. The apparent depth of the tank, when viewed obliquely, is less than the near-normal viewing. (e) Yes The refractive index of diamond (2.42) is more than that of ordinary glass (1.5). The critical angle for diamond is less than that for glass. A diamond cutter uses a large angle of incidence to ensure that the light entering the diamond is totally reflected from its faces. This is the reason for the sparkling effect of a diamond.

33.

Answer the following questions: (a) You have learnt that plane and convex mirrors produce virtual images of objects. Can they produce real images under some circumstances? Explain. (b) A virtual image, we always say, cannot be caught on a screen. Yet when we ‘see’ a virtual image, we are obviously bringing it on to the ‘screen’ (i.e., the retina) of our eye. Is there a contradiction?(c) A diver under water, looks obliquely at a fisherman standing on the bank of a lake. Would the fisherman look taller or shorter to the diver than what he actually is?(d) Does the apparent depth of a tank of water change if viewed obliquely? If so, does the apparent depth increase or decrease?(e) The refractive index of diamond is much greater than that of ordinary glass. Is this fact of some use to a diamond cutter?

Answer»

(a) Yes

Plane and convex mirrors can produce real images as well. If the object is virtual, i.e., if the light rays converging at a point behind a plane mirror (or a convex mirror) are reflected to a point on a screen placed in front of the mirror, then a real image will be formed.

(b) No

A virtual image is formed when light rays diverge. The convex lens of the eye causes these divergent rays to converge at the retina. In this case, the virtual image serves as an object for the lens to produce a real image.
(c) The diver is in the water and the fisherman is on land (i.e., in air). Water is a denser medium than air. It is given that the diver is viewing the fisherman. This indicates that the light rays are travelling from a denser medium to a rarer medium. Hence, the refracted rays will move away from the normal. As a result, the fisherman will appear to be taller.

(d) Yes; Decrease

The apparent depth of a tank of water changes when viewed obliquely. This is because light bends on traveling from one medium to another. The apparent depth of the tank, when viewed obliquely, is less than the near-normal viewing.
(e) Yes

The refractive index of diamond (2.42) is more than that of ordinary glass (1.5). The critical angle for diamond is less than that for glass. A diamond cutter uses a large angle of incidence to ensure that the light entering the diamond is totally reflected from its faces. This is the reason for the sparkling effect of a diamond.

Discussion

34.	Give the Newton’s formula for the speed of sound in air and hence explain Laplace’s correction.
Answer» According to Newton v = √P/ρ

Discussion

35.

Explain types of equilibrium?

Answer»

Equilibrium types	Example
Translation motion	A book resting on a table.
Rotational equilibrium	A body moves in a circular path constant velocity.
Static equilibrium	A wall-hanging, hanging on the wall.
Dynamic equilibrium	A ball decends down in a fluid with its terminal velocity.
Stable equilibrium	A table on the floor.
Unstable equilibrium	A pencil standing on its tip.
Neutral equilibrium	a dice rolling on a game board.

Discussion

36.	Explain the types of equilibrium with suitable examples?
Answer» Translational motion – A book resting on a table. Rotational equilibrium – A body moves in a circular path with constant velocity. Static equilibrium – A wall-hanging, hanging on the wall. Dynamic equilibrium – A ball decends down in a fluid with its terminal velocity. Stable equilibrium – A table on the floor A pencil Unstable equilibrium – standing on its tip. Neutral equilibrium – A dice rolling on a game board.

36.

Explain the types of equilibrium with suitable examples?

Answer»

Translational motion – A book resting on a table.

Rotational equilibrium – A body moves in a circular path with constant velocity.

Static equilibrium – A wall-hanging, hanging on the wall.

Dynamic equilibrium – A ball decends down in a fluid with its terminal velocity.

Stable equilibrium – A table on the floor A pencil

Unstable equilibrium – standing on its tip.

Neutral equilibrium – A dice rolling on a game board.

Discussion

37.	Voltage and current for a circuit with two elements in series are experssed as follows : ν(t) = 170 sin (6280 t + π/3) Volts i(t) = 8.5 sin (6280 t + π/2) Amps (i) Plot the two waveforms. (ii) Determine the frequency in Hz. (iii) Determine the power factor stating its nature. (iv) What are the values of the elements ?
Answer» (i) Two sinusoidal wave forms with a phase-difference of 30° (= π/2 − π/3) are to be drawn. Each waveform completes a cycle in 1 milli-second, since f = 1000 Hz. The waveform for current leads that for the voltage by 30°. At ωt = 0, the current is at its positive peak, while the voltage will be at its positive peak for ωt = π/6 = 30°. Peak value are 170 volts and 8.5 amp. (ii) ω = 6280 radiation/sec, f = ω/2π = 1000 Hz (iii) RMS value of voltage = 170/√2 = 120 volts RMS value of current = 8.5/√2 = 6 amp. Impedance = V/I = 120/6 = 20 ohms Power factor = cos 30°, Leading = 0.866, Since the current leads the voltage, the two elements must be R and C. R = Z cos φ = 20 × 0.866 = 17.32 ohms X_c = Z sinφ = 20 × 0.50 = 10ohms C = 1/(ωX_c) = (1000 x 1000)/(6280 x 10) = 15.92mF

37.

Voltage and current for a circuit with two elements in series are experssed as follows : ν(t) = 170 sin (6280 t + π/3) Volts i(t) = 8.5 sin (6280 t + π/2) Amps (i) Plot the two waveforms. (ii) Determine the frequency in Hz. (iii) Determine the power factor stating its nature. (iv) What are the values of the elements ?

Answer»

(i) Two sinusoidal wave forms with a phase-difference of 30° (= π/2 − π/3) are to be drawn.

Each waveform completes a cycle in 1 milli-second, since f = 1000 Hz.

The waveform for current leads that for the voltage by 30°. At ωt = 0, the current is at its positive peak, while the voltage will be at its positive peak for ωt = π/6 = 30°. Peak value are 170 volts and 8.5 amp.

(ii) ω = 6280 radiation/sec, f = ω/2π = 1000 Hz

(iii) RMS value of voltage = 170/√2 = 120 volts

RMS value of current = 8.5/√2 = 6 amp.

Impedance = V/I = 120/6 = 20 ohms

Power factor = cos 30°, Leading = 0.866,

Since the current leads the voltage, the two elements must be R and C.

R = Z cos φ = 20 × 0.866 = 17.32 ohms

X_c = Z sinφ = 20 × 0.50 = 10ohms

C = 1/(ωX_c) = (1000 x 1000)/(6280 x 10) = 15.92mF

Discussion

38.	Given two current i1 = 10 sin (ωt + π/4) and i2 = 5 cos (ω t − π/2), find the r.m.s. value of i1 + i2 using the complex number representation.
Answer» The maximum value of first current is 10 A and it leads the reference quantity by 45°. The second current can be written as i₂ = 5 cos (ωt − π/2) = 5sin [90 + (ωt − π/2)] = 5 sin ωt Hence, its maximum value is 5 A and is in phase with the reference quantity. ∴ I_m1 = 10 (cos 45° + j sin 45°) = (7.07 + j 7.07) I_m2 = 5 (cos0° + j sin0°) = (5 + j0) The maximum value of resultant current is I_m = (7.07 + j7.07) + (5 + j0) = 12.07 + j7.07 = 14 ∠ 30.4° ∴ R.M.S. value = 14/√2 = 10 A

38.

Given two current i1 = 10 sin (ωt + π/4) and i2 = 5 cos (ω t − π/2), find the r.m.s. value of i1 + i2 using the complex number representation.

Answer»

The maximum value of first current is 10 A and it leads the reference quantity by 45°. The second current can be written as

i₂ = 5 cos (ωt − π/2) = 5sin [90 + (ωt − π/2)] = 5 sin ωt

Hence, its maximum value is 5 A and is in phase with the reference quantity.

∴ I_m1 = 10 (cos 45° + j sin 45°) = (7.07 + j 7.07)

I_m2 = 5 (cos0° + j sin0°) = (5 + j0)

The maximum value of resultant current is

I_m = (7.07 + j7.07) + (5 + j0) = 12.07 + j7.07 = 14 ∠ 30.4°

∴ R.M.S. value = 14/√2 = 10 A

Discussion

39.	Place lenses of focal length 10 cm, 15cm and 20cm on the lens holder without changing the distance between the lens and the screen. On using which lens is the image clear?
Answer» Lens of focal length 10 cm

Discussion

40.	STATEMENT-1: It is easier to pull a heavy object than to push it on a level ground and STATEMENT-2: The magnitude fo frictional force depends on the nature of the two surfaces in contact.A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.B. If both Assertion & Reason are True but Reason is not a correct explanation of the Assertiion.C. If Assertion is True but the Reason is False.D. If both Assertion & Reason are False
Answer» Correct Answer - B

Discussion

41.	To form a jeep, two squares of side length `10cm` & `20cm` and two circles of perimeter `15cm` each are connected as shown. The centre of bigger square is at origin and `x-y` axes are as shown. The `x` coordinate of centre of mass of this model is `:-` A. `x=-5cm`B. `x=-9cm`C. `x=-3cm`D. `x=2cm`
Answer» Correct Answer - A Ans (1) `x=(80xx0+40xx(-15)+15xx(-15)+15xx5)/(80+40+15+15)` `=-5cm`

Discussion

42.	Pull down in the middle a heavy chain, fixed at both ends, in such a way that it forms a triangle. Does the centre of mass takes up a higher or lower position? A. Centre of mass comes downB. Centre of mass goes upC. Centre of mass remains stationaryD. Cannot be predicted
Answer» Correct Answer - B Ans.(2) system always want to maintain the states of lowest PE. So, disturbing the system will result in increase of PE So, potential enery of the system increases, hence centre of mas goes up.

Discussion

43.	In figure, the resistance of galvanometer G is 50 ohm and the battery is ideal. Of the following alternatives, in which case, are the currents arranged strictly in the order of decreasing magnitudes with the larger coming earlier- A. `I,I_(1),I_(g),I_(2)`B. `I,I_(g),I_(1),I_(2)`C. `I,I_(2),I_(1),I_(g)`D. `I_(g),I_(1),I_(2),I`
Answer» Correct Answer - C `(10)/(100)=(1)/(10)` `:. i_(g)=0` As `I prop(1)/(R)` `:. I_(2)gtI_(1)` `:. Igt I_(2)gtI_(1)gtI_(g)`

Discussion

44.	Null point in the galvanometer is obtained when a cell of emf E and internal resisance r is connncted across the length of 22 cm wire of the potentiometer . Now a resistane of `10Omega` is connected across the terminals of the cell (by closing the key K) and null point is obtained against the length of cm. The internal resistance r of the cell is - A. `0.5 Omega`B. `1 Omega`C. ` 1.5 Omega`D. ` 2 Omega`
Answer» Correct Answer - B `r=((l_(1))/(l_(2))-1)R`

Discussion

45.	Portion `AB` of the wedge shown in figure is rough and `BC` is smooth. A solid cylinder rolld without slipping from `A` to `B`. Find the ratio of translational kinetic energy to rotationa linetic energy, when the cylinder reaches point `C`. .A. `3//5`B. 5C. `7//5`D. `8//3`
Answer» Correct Answer - B `K=betaK_(T)` or `K_(T)+K_(R)=betaK_(T)` `K_(R)=(beta-1)K_(T)rArrK_(R)=(1)/(2)K_(T)` At point B: `K_(T)+K_(R)=mgxxh` `:. K_(R)=(mgh)/(3)` At point `C: K_(T)+(mgh)/(3)=mgxx2h` `K_(T)=(5mgh)/(3)` `:. (K_(T))/(K_(R))=5`

Discussion

46.	A carrom board `4ftxx4ft` square has the queen at the centre. The queen hit by the striker moves to the front edge, rebounds and goes in the hole behind the striking line. Find the magnitude of displacement of the queen (a). from the centre to the front edge (b). from the front edge to the hole and (c). from the centre to the hole.
Answer» Correct Answer - (A) `2/3sqrt(10) ft` (B) `4/3sqrt(10)ft` (C) `2sqrt(2) ft` By law of reflection `anglei=angler` `(2-x)/x=4/2rArr 4-2x=xrArr3x=2rArr x=2/3` `vec(A)=(2hat(i))/3+2hat(j), vec(B)=4/3hat(i)-4hat(j), vec(C)=2hat(i)-2hat(j)` `rArr \|A\|=2/3 sqrt(10), \|B\|=4/3 sqrt(10), \|C\|=2sqrt(2)`

Discussion

47.	Let `vec(A)=hat(i)A cos theta+hat(j)A sin theta`, be any vector. Another vector `vec(B)` which is normal to `vec(A)` is :-A. `B costheta hati +B sin thetahatj`B. `B sin theta hati +B cos thetahatj`C. `B sin theta hati - B cos thetahatj`D. `A cos theta hati - A cos thetahatj`
Answer» Correct Answer - C `vec(A)= A cos theta hati +A sin theta J` We must have `vecA.vecB=0,` which is cleaely satisfied by `vec(B) =B sin theta hati -A cos theta hatj.`

Discussion

48.	A motor cycle starts from rest and accelerates along a straight path at `2m//s^(2)`. At the starting point of the motor cycle there is a stationary electric siren. How far has the motor cycle gone when the driver hears the frequency of the siren at `94%` of its value when the motor cycle was at rest ? (Speed of sound = `330ms^(-2))`A. 49 mB. 98 mC. 147 mD. 196 m
Answer» Correct Answer - B when source in stationary and observer is moving away from the source . ` n^(t) =n((V-V_(0))/(V))` `implies 0.94 n=n((330-V_(0))/(330))` ` implies V_(0) =19.8 m//s` `therefore V_(0)=0+2as` ` therefore S=(V_(0)^(2))/(2a)` `=(19.8xx19.8)/(2xx2)` =98 m.

Discussion

49.	A slit of width is illuminated by white light. For red light `(lambda=6500Å)`, the first minima is obtained at `theta=30^@`. Then the value of will beA. `3250Å`B. `6.5 xx 10^(-4)cm`C. `1.3` micronD. `2.6 xx 10^(-4)cm`
Answer» Correct Answer - C `sin theta = (n lambda)/(a)`, for `n =1, sin theta = (lambda)/(a)` `:. a = (lambda)/(sin theta) = (6500 xx 10^(-10))/(sin 30^(@))` `a = 13000 xx 10^(-10)m` `a = 1.3 xx 10^(-6)m` `a = 1.3` micron

Discussion

50.	A particle is revolving in a circular path as shownin figure in the horizontal plane such that the angular velocity of the particle about the point O is constant and is equal to `1 rad//s`. Distance of the particle from O is given by`R=R_(0)-betat` where `R_(0)`and `Beta` are constant. The speed ofthe particle,as afunction of time is: ltbrlt A. `sqrt(beta^(2)+1)`B. `(R_(0)+beta t)`C. `beta`D. `sqrt(beta^(2)+(R_(0)+beta t)^(2))`
Answer» Correct Answer - D

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

If the distance between the points (2, 3) and (a, 0) is 3 then a = ______(A) 2 (B) 3 (C) 5 (D) 1

The median of a set of `9` distinct observations is `20.5`. If each of the largest `4` observations of the set is increased by `2`, then the median of the new setA. is incrased by `2`B. is decreased by `2`C. is two times the original medianD. remains the same as that of the original set

If `A(1,p^(2)),B(0,1)` and `C(p,0)` are the coordinates of three points then area of the triangle `ABC` is `1/(lamda)|p^(3)-p+1|`. The value of `lamda` is

If `A=[{:(1,-1,1),(0,2,-3),(2,1,0):}]` and `B=(adjA)` and `C=5A`, then find the value of `(|adjB|)/(|C |)`

If discriminant of f(x) = ax2 + bx + c is negative and a + b + c > 0 then find whether the Quadratic function is opening upward or opening downwards.

The simplified value of cosθ secθ + sinθ cosθ is (A) 2 (B) 3 (C) 0 (D) 1

Find:The 10th term of the G.P. √2, \(\frac{1}{\sqrt{2}}, \frac{1}{2\sqrt{2}}\),........

If sin cos⁻¹ (1 + x) = cos tan⁻¹ x then x is.

If \( u=\log \left(x^{2}+y^{2}+z^{2}\right) \), then the value of \( x u_{x}+y u_{y}+z u_{z} \) is equal to

What _ the weather _ in Las Vegas the day before yesterday. A) were / like B) was/as C) is / like D) was/like

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If the sequence of the coding strand in a transcription unit is written asfollows:5'-ATGCATGCATGCATGCATGCATGCATGC-3'. Write down thesequence of mRNA.

Which of the following is correct order for basic nature?A. `CH_(3)FgtCH_(3)OHgtCH_(3)NH_(2)`B. `CH_(3)FgtCH_(3)NH_(2)gtCH_(3)OH`C. `CH_(3)NH_(2)gtCH_(3)FgtCH_(3)OH`D. `CH_(3)NH_(2)gtCH_(3)OHgtCH_(3)F`

What are the salient features of valence bond theroy (VBT) ?

Which set represents interamolecular redox changes? `1. 2KClO_(3)to 2KCl+3O_(2)` `2.(NH_(4))_(2)Cr_(2)O_(7)toN_(2)+Cr_(2)O_(3)+4H_(2)O` `3. Cl_(2)+OH^(-)toClO^(-)+Cl^(-)+H^(+)` `4. Mn_(2)O_(7)to2MnO_(2)+3//2O_(2)`A. `1,2,4`B. `1,2,3`C. `3,4`D. `2,3`

A heavy weight is suspended from a spring Te energy stored in the spring is E. If the weight is raised till the spring comes to its stretched position and the work done in doing so be W. then gain in gravitational potential energy of the weight will be : (A) W + E (B) W – E (C) W(D) E

National Highway 44 originates from which district of Rajasthan?1. Sawai Madhopur2. Dausa3. Dholpur4. Karauli

factors influencing the heat developed when a current passes through a conductor.

Correct the mistakes, if any:a. Amperage decreases in proportion to the decrease in the area of cross-section of the conductor.b. Connecting appliances in a circuit beyond its power capacity is short circuit.c. It is to reduce the heat loss that electric lamps are filled with inert gases.

Light of a certain wavelength has a wave number `barv` in vacum. Its wave number in a medium of refractive index n isA. `n/v`B. `(1)/(n barv)`C. `(barv)/(n)`D. `n barv`

A concave mirror produces three times magnified real image of an object placed at 10 cm in front of it. Where is the image located?

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Give the Newton’s formula for the speed of sound in air and hence explain Laplace’s correction.

Explain types of equilibrium?

Explain the types of equilibrium with suitable examples?

Given two current i1 = 10 sin (ωt + π/4) and i2 = 5 cos (ω t − π/2), find the r.m.s. value of i1 + i2 using the complex number representation.

Place lenses of focal length 10 cm, 15cm and 20cm on the lens holder without changing the distance between the lens and the screen. On using which lens is the image clear?

To form a jeep, two squares of side length `10cm` & `20cm` and two circles of perimeter `15cm` each are connected as shown. The centre of bigger square is at origin and `x-y` axes are as shown. The `x` coordinate of centre of mass of this model is `:-` A. `x=-5cm`B. `x=-9cm`C. `x=-3cm`D. `x=2cm`

Pull down in the middle a heavy chain, fixed at both ends, in such a way that it forms a triangle. Does the centre of mass takes up a higher or lower position? A. Centre of mass comes downB. Centre of mass goes upC. Centre of mass remains stationaryD. Cannot be predicted

Portion `AB` of the wedge shown in figure is rough and `BC` is smooth. A solid cylinder rolld without slipping from `A` to `B`. Find the ratio of translational kinetic energy to rotationa linetic energy, when the cylinder reaches point `C`. .A. `3//5`B. 5C. `7//5`D. `8//3`

Let `vec(A)=hat(i)A cos theta+hat(j)A sin theta`, be any vector. Another vector `vec(B)` which is normal to `vec(A)` is :-A. `B costheta hati +B sin thetahatj`B. `B sin theta hati +B cos thetahatj`C. `B sin theta hati - B cos thetahatj`D. `A cos theta hati - A cos thetahatj`

A slit of width is illuminated by white light. For red light `(lambda=6500Å)`, the first minima is obtained at `theta=30^@`. Then the value of will beA. `3250Å`B. `6.5 xx 10^(-4)cm`C. `1.3` micronD. `2.6 xx 10^(-4)cm`

Explore topic-wise InterviewSolutions in Current Affairs.

If the distance between the points (2, 3) and (a, 0) is 3 then a = ______(A) 2 (B) 3 (C) 5 (D) 1

The median of a set of `9` distinct observations is `20.5`. If each of the largest `4` observations of the set is increased by `2`, then the median of the new setA. is incrased by `2`B. is decreased by `2`C. is two times the original medianD. remains the same as that of the original set

If `A(1,p^(2)),B(0,1)` and `C(p,0)` are the coordinates of three points then area of the triangle `ABC` is `1/(lamda)|p^(3)-p+1|`. The value of `lamda` is

If `A=[{:(1,-1,1),(0,2,-3),(2,1,0):}]` and `B=(adjA)` and `C=5A`, then find the value of `(|adjB|)/(|C |)`

If discriminant of f(x) = ax2 + bx + c is negative and a + b + c &gt; 0 then find whether the Quadratic function is opening upward or opening downwards.

The simplified value of cosθ secθ + sinθ cosθ is (A) 2 (B) 3 (C) 0 (D) 1

Find:The 10th term of the G.P. √2, \(\frac{1}{\sqrt{2}}, \frac{1}{2\sqrt{2}}\),........

If sin cos⁻¹ (1 + x) = cos tan⁻¹ x then x is.

If \( u=\log \left(x^{2}+y^{2}+z^{2}\right) \), then the value of \( x u_{x}+y u_{y}+z u_{z} \) is equal to

What _____ the weather _____ in Las Vegas the day before yesterday. A) were / like B) was/as C) is / like D) was/like

Famous 'Kamakhya Devi Temple' is located in which state?1. Assam2. Madhya Pradesh3. Himachal Pradesh4. Karnataka

If the sequence of the coding strand in a transcription unit is written asfollows:5'-ATGCATGCATGCATGCATGCATGCATGC-3'. Write down thesequence of mRNA.

Which of the following is correct order for basic nature?A. `CH_(3)FgtCH_(3)OHgtCH_(3)NH_(2)`B. `CH_(3)FgtCH_(3)NH_(2)gtCH_(3)OH`C. `CH_(3)NH_(2)gtCH_(3)FgtCH_(3)OH`D. `CH_(3)NH_(2)gtCH_(3)OHgtCH_(3)F`

What are the salient features of valence bond theroy (VBT) ?

Which set represents interamolecular redox changes? `1. 2KClO_(3)to 2KCl+3O_(2)` `2.(NH_(4))_(2)Cr_(2)O_(7)toN_(2)+Cr_(2)O_(3)+4H_(2)O` `3. Cl_(2)+OH^(-)toClO^(-)+Cl^(-)+H^(+)` `4. Mn_(2)O_(7)to2MnO_(2)+3//2O_(2)`A. `1,2,4`B. `1,2,3`C. `3,4`D. `2,3`

A heavy weight is suspended from a spring Te energy stored in the spring is E. If the weight is raised till the spring comes to its stretched position and the work done in doing so be W. then gain in gravitational potential energy of the weight will be : (A) W + E (B) W – E (C) W(D) E

National Highway 44 originates from which district of Rajasthan?1. Sawai Madhopur2. Dausa3. Dholpur4. Karauli

factors influencing the heat developed when a current passes through a conductor.

Correct the mistakes, if any:a. Amperage decreases in proportion to the decrease in the area of cross-section of the conductor.b. Connecting appliances in a circuit beyond its power capacity is short circuit.c. It is to reduce the heat loss that electric lamps are filled with inert gases.

Light of a certain wavelength has a wave number `barv` in vacum. Its wave number in a medium of refractive index n isA. `n/v`B. `(1)/(n barv)`C. `(barv)/(n)`D. `n barv`

A concave mirror produces three times magnified real image of an object placed at 10 cm in front of it. Where is the image located?

(a) a concave mirror(b) a convex mirror(c) a plane mirror(d) both concave as well as plane mirror

A virtual image larger than the object can be obtained by(a) concave mirror (b) convex mirror(c) plane mirror (d) concave lens

Give the Newton’s formula for the speed of sound in air and hence explain Laplace’s correction.

Explain types of equilibrium?

Explain the types of equilibrium with suitable examples?

Given two current i1 = 10 sin (ωt + π/4) and i2 = 5 cos (ω t − π/2), find the r.m.s. value of i1 + i2 using the complex number representation.

Place lenses of focal length 10 cm, 15cm and 20cm on the lens holder without changing the distance between the lens and the screen. On using which lens is the image clear?

To form a jeep, two squares of side length `10cm` & `20cm` and two circles of perimeter `15cm` each are connected as shown. The centre of bigger square is at origin and `x-y` axes are as shown. The `x` coordinate of centre of mass of this model is `:-` A. `x=-5cm`B. `x=-9cm`C. `x=-3cm`D. `x=2cm`

Pull down in the middle a heavy chain, fixed at both ends, in such a way that it forms a triangle. Does the centre of mass takes up a higher or lower position? A. Centre of mass comes downB. Centre of mass goes upC. Centre of mass remains stationaryD. Cannot be predicted

Portion `AB` of the wedge shown in figure is rough and `BC` is smooth. A solid cylinder rolld without slipping from `A` to `B`. Find the ratio of translational kinetic energy to rotationa linetic energy, when the cylinder reaches point `C`. .A. `3//5`B. 5C. `7//5`D. `8//3`

Let `vec(A)=hat(i)A cos theta+hat(j)A sin theta`, be any vector. Another vector `vec(B)` which is normal to `vec(A)` is :-A. `B costheta hati +B sin thetahatj`B. `B sin theta hati +B cos thetahatj`C. `B sin theta hati - B cos thetahatj`D. `A cos theta hati - A cos thetahatj`

A slit of width is illuminated by white light. For red light `(lambda=6500Å)`, the first minima is obtained at `theta=30^@`. Then the value of will beA. `3250Å`B. `6.5 xx 10^(-4)cm`C. `1.3` micronD. `2.6 xx 10^(-4)cm`

If discriminant of f(x) = ax2 + bx + c is negative and a + b + c > 0 then find whether the Quadratic function is opening upward or opening downwards.

What _ the weather _ in Las Vegas the day before yesterday. A) were / like B) was/as C) is / like D) was/like