100525 + Interview Questions in GENERAL QA IN GENERAL AWARENESS

1.	If a pole 6 meter high casts a shadow 2√3 meter long on ground, then the angle of elevation of sun is –(A) 15° (B) 30°(C) 45°(D) 60°
Answer» Correct answer is (D) 60°

Discussion

2.	When you walk through a metal detector carrying a metal object in your pocket, it raises an alarm. This phenomenon works on (A) Electromagnetic induction(B) Resonance in ac circuits(C) Mutual induction in ac circuits(D) interference of electromagnetic waves
Answer» Correct option is (B) Resonance in ac circuits Metal detector works on the principle of transmitting an electromagnetic signal and analyses a return signal from the target. So it works on the principle of resonance in AC circuit.

2.

When you walk through a metal detector carrying a metal object in your pocket, it raises an alarm. This phenomenon works on (A) Electromagnetic induction(B) Resonance in ac circuits(C) Mutual induction in ac circuits(D) interference of electromagnetic waves

Answer»

Correct option is (B) Resonance in ac circuits

Metal detector works on the principle of transmitting an electromagnetic signal and analyses a return signal from the target. So it works on the principle of resonance in AC circuit.

Discussion

3.	A cuboid of height 10 cm, width 5 cm and 8 kg is kept on a rough horizontal ground as shown . The ground is so rough that we can assume that the questions indicated below. A boy applies a horizontal force F at the top edge of the cuboid. IF the force applied is 2F, what is the initial angular acceleration of the cuboid ?A. `60 rad//s^(2)`B. `30 rad//s^(2)`C. `15 rad//s^(2)`D. `240 rad//s^(2)`
Answer» Correct Answer - A `Fxx0.1-mgxx0.05/2=Ialpha` `I=M/3(omega^(2)+h^(2))=8/3(25/(10^(4))+100/(10^(4)))` `=1/30 kg-m^(2)` `L=(4-80xx1//40)/(1//30) =60 rad//s^(2)`

Discussion

4.	“Wages as a sum of money are paid under contract by an employer to a worker for services rendered.” Who said this? (a) Benham (b) Marshall (c) Walker (d) J. S. Mill
Answer» Correct Answer is: (a) Benham

Discussion

5.	(186) a country needs money for a development project, what can it do? It can (187) to the World Bank or Asian Development Bank for aid. A country with a foreign currency problem can ask the International Monetary Fund for (188). However, (189) there is no way out for a country which has shortage of food. The country cannot (190) import the food if it is rare like pulses which are grown only by a few countries in such cases the problem is more (191). This situation has led experts to suggest the (192) of establishing a World Agricultural Bank. The food situation today is serious since production is not keeping (193) with demand. The World Agricultural Bank can therefore be established by member-countries who have to (194) both capital as well as surplus food to the Bank. The stocks would form a corpus which would be used to assist members in (195) of distress.A. controlsB. combatsC. timesD. needs
Answer» Correct Answer - C

Discussion

6.	My sister has graduated from the University. A) So is my sister B) Her sister has either C) So has his brother D) Neither did mine E) So do they
Answer» Correct option is C) So has his brother

Discussion

7.	Recently I visited Moscow, a Russian city (216) many war memorials. There is a huge park in Russia (217) as Peace Park. In the middle of the park (218) a pillar on which the different battles fought by the Russians have been mentioned alongwith the names and the places. As I was standing under a tree my eyes (219) on a young couple who had been just married. I started wondering (220) they had come to this monument on their wedding day.A. hasB. builtC. withD. erected
Answer» Correct Answer - C

Discussion

8.	She has lived in Moscow for 20 years. - ___ . A) I do too. B) So do I. C) I have too. D) So have I. E) Neither have I.
Answer» Correct option is D) So have I.

Discussion

9.	Recently I visited Moscow, a Russian city (216) many war memorials. There is a huge park in Russia (217) as Peace Park. In the middle of the park (218) a pillar on which the different battles fought by the Russians have been mentioned alongwith the names and the places. As I was standing under a tree my eyes (219) on a young couple who had been just married. I started wondering (220) they had come to this monument on their wedding day.A. ifB. whereC. aboutD. why
Answer» Correct Answer - D

Discussion

10.	Assertion: Greenhouse effect was observed in houses used to grow plants and these are made of green glass. Reason: Greebhouse name has been given because glass are of green glass.A. (a)If both assertion and reason are true and the reason is the correct explanation of the assertion.B. (b)If both assertion and reason are true and the reason is not the correct explanation of the assertion.C. (c )If assertion is true but reason is false.D. (d)If assertion is false but reason is true.
Answer» Correct Answer - A Greenhouse effect was observed in houses used to grow plant in colder regions. Since the house were made up of green glasses, these are called greenhouses. Note: Similar phenomenon is also seen in our environment which keeps our earth warm and makes life possible on it. This effect is called greenhouse effect.

Discussion

11.	I visited my sister when she ___ in Moscow. A) lived B) lives C) were lived D) is living E) were living
Answer» Correct option is A) lived

Discussion

12.	The greatest affinity for haemoglobin is shown by (a) NO (b) CO (c) O2 (d) CO2
Answer» The greatest affinity for haemoglobin is shown by CO

Discussion

13.	Choose the appropriate answers for the following questions.Whom do you often write letters to? A) To England B) To Moscow C) My friends do D) To my pen-friend E) My pen-friend does
Answer» Correct option is D) To my pen-friend

Discussion

14.	Pete ____ by the time the meeting starts. A) arrived B) had arrived C) will have arrived D) has arrived
Answer» Correct option is C) will have arrived

Discussion

15.	Choose the appropriate answers for the following questions.Who has cut the hand? A) I did B) He has C) Pete does D) Ann had E) The knife had
Answer» Correct option is B) He has

Discussion

16.	Name the non metal which exists in liquid form at room temperature. a) Oxygen b) Hydrogen c) Bromine d) Mercury
Answer» Bromine non metal which exists in liquid form at room temperature.

Discussion

17.	Indicate the number of unpaired electrons in: a. `P, b. Si, c. Cr`, d. `Fe, e. Kr`
Answer» a. `._(15)P=1s^(2)2s^(2)2p^(6)3s^(2)3p_(x)^(1)3p_(y)^(1)3p_(z)^(1)` Number of unpaired electron `=3` b. `._(14)Si=1s^(2)2s^(2)2p^(6)3s^(2)3p_(x)^(1)3p_(y)^(1)` Number of unpaired electron `=2` c. `._(24)Cr=1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)3d^(5)4s^(1)` Number of unpaired electron `=6` d. `._(26)Fe=1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)3d^(6)4s^(2)` Number of unpaired electron `=4("in" 3d).` e. `._(36)Kr=` Noble gas. All orbitals are filled. Unpaired electrons `=0`.

Discussion

18.	Name the metal which can be cut with knife. a) Sodium b) Sulphur c) Iron d) Zinc
Answer» Sodium metal which can be cut with knife.

Discussion

19.	Which of the following is not a preservative? a) Sodium meta bisulphate b) Sodium chloride c) Sodium benzoate d) Sodium Carbonate
Answer» Sodium Carbonate is not a preservative.

Discussion

20.	The ratio of longest and shortest wavelenghths of lyman series is
Answer» The ratio of the longest and shortest wavelength of the Lyman series is 4/3

Discussion

21.	How many hybrid orbitals can form from one 1s orbital and two 2p orbitals?
Answer» ONLY ONE HYBRID ORBITAL WILL FORM FROM ONE 1 S ORBITAL AND TWO 2 P ORBITALS THE HYBRID ORBITAL WILL BE sp²

21.

How many hybrid orbitals can form from one 1s orbital and two 2p orbitals?

Answer»

ONLY ONE HYBRID ORBITAL WILL FORM FROM ONE 1 S ORBITAL AND TWO 2 P ORBITALS

THE HYBRID ORBITAL WILL BE sp²

Discussion

22.	Find the equation of the radical axis of x2 + y2 – 2x – 4y – 1= 0, x2 + y2 – 4x – 6y + 5 = 0.
Answer» S – S' = 0 radical axis (x² + y² – 2x – 4y – 1) – (x² + y² – 4x – 6y + 5) = 0 2x + 2y – 6 = 0 (or) x + y – 3 = 0

22.

Find the equation of the radical axis of x2 + y2 – 2x – 4y – 1= 0, x2 + y2 – 4x – 6y + 5 = 0.

Answer»

S – S' = 0 radical axis

(x² + y² – 2x – 4y – 1) – (x² + y² – 4x – 6y + 5) = 0

2x + 2y – 6 = 0 (or)

x + y – 3 = 0

Discussion

23.	Find the product of lengths of the perpendiculars from any point on the hyperbola x2/16 - y2/9 = 1 to its asymptotes.
Answer» Equation of the hyperbola is x²/16 – y²/9 = 1 a² = 16, b² = 9 Product of the perpendiculars from any point as the hyperbola to its asymptotes = a² b²/a² + b²= 16 x 9/16 + 9 = 144/25

23.

Find the product of lengths of the perpendiculars from any point on the hyperbola x2/16 - y2/9 = 1 to its asymptotes.

Answer»

Equation of the hyperbola is x²/16 – y²/9 = 1

a² = 16, b² = 9

Product of the perpendiculars from any point as the hyperbola to its asymptotes

= a² b²/a² + b²= 16 x 9/16 + 9 = 144/25

Discussion

24.	A double ordinate of the curve y2 = 4ax is of length 8a prove that the lines from the vertex to its ends are at right angles.
Answer» Let P = (at², 2at) and P' = (at², –2at) be the ends of double cordinate PP'. Then 8a = PP' = √(0 + (4at)²) = 4at ⇒ t = 2. ∴ P = (4a, 4a), P' = (4a, –4a) Slope of bar(AP) × slope of bar(AP') (4a/4a)(- 4a/4a) = –1 ∴ ∠PAP' = π/2.

24.

A double ordinate of the curve y2 = 4ax is of length 8a prove that the lines from the vertex to its ends are at right angles.

Answer»

Let P = (at², 2at) and P' = (at², –2at) be the ends of double cordinate PP'.

Then

8a = PP' = √(0 + (4at)²) = 4at ⇒ t = 2.

∴ P = (4a, 4a), P' = (4a, –4a)

Slope of bar(AP) × slope of bar(AP')

(4a/4a)(- 4a/4a) = –1

∴ ∠PAP' = π/2.

Discussion

25.	All of the angles of a quadrilateral are congruent. Can the quadrilateral be a parallelogram?
Answer» It depends on the size of each angle. If a parallelogram has the same sizes of the quadrilateral then they could both be congruent.

Discussion

26.	Assertion (A) : Time period of a hollow ball will be more than that of a solid ball of same radius. Reason (R ) : Time period is independence of mass or distribuiton but on `sqrt(l)`, where `l` is the distance between the point of suspension and the centre of the bob.A. Assertion is True, Reason is True, Reason is correct explanation for Assertion.B. Assertion is True, Reason is True, Reason is not correct explanation for Assertion.C. Assertion is True, Reason is False.D. Assertion is False, Reason is True.
Answer» Correct Answer - D Assertion is false, since effective length is not altered. Reason is true since `T=2pisqrt((l)/(g))` So, choice (`d`) is correct.

Discussion

27.	In an experiment of simple pendulum, time period measured was `50s` for `25` vibrations when the length of the simple pendulum was taken to be `100cm`. If the lest count of stop watch is `0.1s` and that of metre scale is `0.1 cm`, calculate the maximum possible percentage error in the measurement of value of `g`.
Answer» Correct Answer - 0.5 The time period of a simple pendulum is given by `T=2pisqrt((l)/(g))` or `T^(2)=(4pi^(2)l)/(g)` or `g=(4pi^(2)l)/(T^(2))` As `4` and `pi` are constants, maximum permissible error in `g` is given by `(Deltag)/(g)=(Deltal)/(l)+(2DeltaT)/(T)` Here, `Deltal=0.1cm`, `l=1m=100cm`, `DeltaT=0.1s`, `T=50s` `:. (Deltag)/(g)=(0.1)/(100)+2((0.1)/(50))=(0.1)/(100)+((0.1)/(25))` or `(Deltag)/(g)xx100=((0.1)/(100)+(0.1)/(25))xx100` `=0.1+0.4=0.5%`

Discussion

28.	What name is given to carbon reduction process for extracting the metal?
Answer» Correct Answer - Smelting.

Discussion

29.	A spherical mirror produces an image of magnification -1 on a screen placed at a distance of 50 cm from the mirror i) write the type of mirror usedii) find the distance of the image from the imageiii) what is the focal length of the mirror
Answer» It's concave mirror m= -v/u=-1 =>v=50 1/v+1/u=1/f=> f=25

Discussion

30.	When is electrolytic reduction applied for getting a metal?
Answer» For extraction of very active metal, e.g., Na, Ca etc. Where other methods cannot be used.

Discussion

31.	The essential component of a toaster is an electrical element (a resistor) that converts electrical energy to heat energy. How much current is drawn by a toaster with resistance 12Ω at 110V?
Answer» current drawn by resistance 9.167 A

31.

The essential component of a toaster is an electrical element (a resistor) that converts electrical energy to heat energy. How much current is drawn by a toaster with resistance 12Ω at 110V?

Answer»

current drawn by resistance

9.167 A

Discussion

32.	An electrical iron carrying 2A at 120V. Find resistance of the device?
Answer» \(R = \frac{v}{i}\) \(= \frac{120}{2}\) \(= 60 \Omega\)

32.

An electrical iron carrying 2A at 120V. Find resistance of the device?

Answer»

\(R = \frac{v}{i}\)

\(= \frac{120}{2}\)

\(= 60 \Omega\)

Discussion

33.	Name the method of metal refining which is generally used when a metal of high degree of purity is needed.
Answer» Correct Answer - Zone refining.

Discussion

34.	A voltage source of 20Sinπt V is connected across a 5KΩ resistor. Find the current through the resistor and power dissipated.
Answer» \(I=\frac{V}{R}=4Sin(\pi t)mA\) \(P=VI=80Sin^2(\pi t)mW\)

34.

A voltage source of 20Sinπt V is connected across a 5KΩ resistor. Find the current through the resistor and power dissipated.

Answer»

\(I=\frac{V}{R}=4Sin(\pi t)mA\)

\(P=VI=80Sin^2(\pi t)mW\)

Discussion

35.	Give reasons for the following: (a) Transition elements and their compounds act as catalysts. (b) Eo value for (Mn2+\|Mn) is negative whereas for (Cu2+\| Cu) + is positive. (c) Actinoids show irregularities in their electronic configuration.
Answer» (a) The catalytic properties of transition metals are attributed to their ability to exist in multiple oxidation states and form complexes. Variable oxidation states make them more efficient catalysts. (b) The electronic configuration of Mn²⁺ is d⁵ which is more stable because of half-filled d-subshell. While Cu²⁺ with electronic configuration d⁹ becomes stable after accepting two electrons with configuration d¹⁰ s¹ due to fully-filled d-orbital. (c) The elements Th (At. no. 90) to Lr (At. no. 103) are together known as actinoids. For the first four actinoids Th, Pa, U and Np, the difference between the energy levels of 5f and 6d orbitals is small. Thus, in these elements (or ions) electrons may occupy either 5d or 6f orbitals.

35.

Give reasons for the following: (a) Transition elements and their compounds act as catalysts. (b) Eo value for (Mn2+|Mn) is negative whereas for (Cu2+| Cu) + is positive. (c) Actinoids show irregularities in their electronic configuration.

Answer»

(a) The catalytic properties of transition metals are attributed to their ability to exist in multiple oxidation states and form complexes. Variable oxidation states make them more efficient catalysts.

(b) The electronic configuration of Mn²⁺ is d⁵ which is more stable because of half-filled d-subshell. While Cu²⁺ with electronic configuration d⁹ becomes stable after accepting two electrons with configuration d¹⁰ s¹ due to fully-filled d-orbital.

(c) The elements Th (At. no. 90) to Lr (At. no. 103) are together known as actinoids. For the first four actinoids Th, Pa, U and Np, the difference between the energy levels of 5f and 6d orbitals is small. Thus, in these elements (or ions) electrons may occupy either 5d or 6f orbitals.

Discussion

36.	For a reaction2H2O2\(\frac{I^-}{\text{alkaline medium}}\to\)2H2O+O2 the proposed mechanism is as given below: (I) H2O2 + I– → H2O + IO– (slow) (II) H2O2 + IO– → H2O + I– + O2 (fast) (a) Write rate law for the reaction. (b) Write the overall order of reaction. (c) Out of steps (I) and (II), which one is rate determining step?
Answer» The reactions given are as follows: 2H₂O_{2\(\frac{I^-}{\text{alkialine medium}}\to\)}2H₂O+O₂ H₂O₂+I^-→H₂O+IO^-(slow) (i) H₂O₂+IO^-→H₂O+I^-+O₂(fast) (ii) (a) To find the rate expression, we consider rate determining step, which is step (I) for this reaction. Then according to the rate law, Rate=k[H₂O₂][I^-] (b) Since, two reagents are involved in the rate-limiting step, thus overall rate of reaction is proportional to the concentration of those reagents, that is, 2. (c) The slowest step in this reaction is called the rate-determining step, that is step (I).

36.

For a reaction2H2O2\(\frac{I^-}{\text{alkaline medium}}\to\)2H2O+O2 the proposed mechanism is as given below: (I) H2O2 + I– → H2O + IO– (slow) (II) H2O2 + IO– → H2O + I– + O2 (fast) (a) Write rate law for the reaction. (b) Write the overall order of reaction. (c) Out of steps (I) and (II), which one is rate determining step?

Answer»

The reactions given are as follows:

2H₂O_{2\(\frac{I^-}{\text{alkialine medium}}\to\)}2H₂O+O₂

H₂O₂+I^-→H₂O+IO^-(slow) (i)

H₂O₂+IO^-→H₂O+I^-+O₂(fast) (ii)

(a) To find the rate expression, we consider rate determining step, which is step (I) for this reaction. Then according to the rate law,

Rate=k[H₂O₂][I^-]

(b) Since, two reagents are involved in the rate-limiting step, thus overall rate of reaction is proportional to the concentration of those reagents, that is, 2.

(c) The slowest step in this reaction is called the rate-determining step, that is step (I).

Discussion

37.	What is the basic structural difference between glucose and fructose?
Answer» Glucose contains aldehydic functional group while fructose contains ketonic functional group

Discussion

38.	Write the products obtained after hydrolysis of lactose
Answer» Lactose+Water ^{\(\underline{{H^+\text{or Lactase}}}_\to\)}Galactose + Glucose

Discussion

39.	The molecular formula of an ester is C3 H7 COOC2 H5. Write the molecular formula of the alcohol and the acid from which it might be prepared.
Answer» Alochol formed from ester C₃H₇ COOC₂ H₅ is C₂H₅ OH and acid formed is C₃ H₇ COOH.

Discussion

40.	compound most reactive towards SN1 reaction
Answer» Correct answer will be option (C) SN1 reactions proceed via the formation of a carbocation intermediate. More stable is the carbocation more reactive is the alkyl/aryl halide towards SN1.

Discussion

41.	A voltage signal source of constant amplitude with frequency varying from dc to 25 kHz is applied to a low-pass filter. Which frequency will develop greatest voltage across the output load resistance? (a) d.c. (b) 10 kHz (c) 15 kl (d) 25 kHz
Answer» Correct option (a) d.c.

41.

A voltage signal source of constant amplitude with frequency varying from dc to 25 kHz is applied to a low-pass filter. Which frequency will develop greatest voltage across the output load resistance? (a) d.c. (b) 10 kHz (c) 15 kl (d) 25 kHz

Answer»

Correct option (a) d.c.

Discussion

42.	A network which attenuate a single band of frequencies and allows those on either side to pass through is called ........ filter.(a) low-pass (b) high-pass (c) band stop (d) band pass
Answer» Correct option (c) band stop

42.

A network which attenuate a single band of frequencies and allows those on either side to pass through is called ........ filter.(a) low-pass (b) high-pass (c) band stop (d) band pass

Answer»

Correct option (c) band stop

Discussion

43.	The decibel is a measure of (a) power (b) voltage (c) current (d) power level
Answer» (d) power level

Discussion

44.	The frequency corresponding to half-power point on the response curve of a filter is known as — (a) cutoff (b) upper (c) lower (d) roll-off
Answer» Correct option (a) cutoff

44.

The frequency corresponding to half-power point on the response curve of a filter is known as — (a) cutoff (b) upper (c) lower (d) roll-off

Answer»

Correct option (a) cutoff

Discussion

45.	In a simple low-pass RC filter, attenuation is – 3 dB at fc. At 2 fc , attenuation is – 6 dB. At 10 f c, the attenuation would be .... dB. (a) – 30 (b) – 20 (c) – 18 (d) – 12
Answer» Correct option (b) – 20

45.

In a simple low-pass RC filter, attenuation is – 3 dB at fc. At 2 fc , attenuation is – 6 dB. At 10 f c, the attenuation would be .... dB. (a) – 30 (b) – 20 (c) – 18 (d) – 12

Answer»

Correct option (b) – 20

Discussion

46.	In an RL low-pass filter, an attenuation of – 12 dB/octave corresponds to ........... dB/ decade. (a) – 6 (b) – 12 (c) – 20 (d) – 40
Answer» Correct option (d) – 40

46.

In an RL low-pass filter, an attenuation of – 12 dB/octave corresponds to ........... dB/ decade. (a) – 6 (b) – 12 (c) – 20 (d) – 40

Answer»

Correct option (d) – 40

Discussion

47.	In a simple high-pass RC filter, if the value of capacitance is doubled, the cutoff frequency is (a) doubled (b) halved (c) tripled (d) quadrupled
Answer» Correct option (b) halved

47.

In a simple high-pass RC filter, if the value of capacitance is doubled, the cutoff frequency is (a) doubled (b) halved (c) tripled (d) quadrupled

Answer»

Correct option (b) halved

Discussion

48.	When two simple low-pass filters having same values of R and C are cascaded, the combined filter will have a roll-off of ...... dB/decade. (a) – 20 (b) – 12 (c) – 40 (d) – 36
Answer» Correct option (c) – 40

48.

When two simple low-pass filters having same values of R and C are cascaded, the combined filter will have a roll-off of ...... dB/decade. (a) – 20 (b) – 12 (c) – 40 (d) – 36

Answer»

Correct option (c) – 40

Discussion

49.	An a.c. signal of constant voltage 10 V and variable frequency is applied to a simple high-pass RC filter. The output voltage at ten times the cutoff frequency would be ............... volt. (a) 1 (b) 5 (c) 10/√2 (d) 10√2
Answer» Correct option (a) 1

49.

An a.c. signal of constant voltage 10 V and variable frequency is applied to a simple high-pass RC filter. The output voltage at ten times the cutoff frequency would be ............... volt. (a) 1 (b) 5 (c) 10/√2 (d) 10√2

Answer»

Correct option (a) 1

Discussion

50.	In a simple high-pass RL filter circuit, the phase difference between the output and input voltages at the cutoff frequency is .... degrees. (a) – 90 (b) 45 (c) – 45 (d) 90
Answer» Correct option (b) 45

50.

In a simple high-pass RL filter circuit, the phase difference between the output and input voltages at the cutoff frequency is .... degrees. (a) – 90 (b) 45 (c) – 45 (d) 90

Answer»

Correct option (b) 45

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

If a pole 6 meter high casts a shadow 2√3 meter long on ground, then the angle of elevation of sun is –(A) 15° (B) 30°(C) 45°(D) 60°

When you walk through a metal detector carrying a metal object in your pocket, it raises an alarm. This phenomenon works on (A) Electromagnetic induction(B) Resonance in ac circuits(C) Mutual induction in ac circuits(D) interference of electromagnetic waves

“Wages as a sum of money are paid under contract by an employer to a worker for services rendered.” Who said this? (a) Benham (b) Marshall (c) Walker (d) J. S. Mill

My sister has graduated from the University. A) So is my sister B) Her sister has either C) So has his brother D) Neither did mine E) So do they

She has lived in Moscow for 20 years. - ___ . A) I do too. B) So do I. C) I have too. D) So have I. E) Neither have I.

I visited my sister when she ___ in Moscow. A) lived B) lives C) were lived D) is living E) were living

The greatest affinity for haemoglobin is shown by (a) NO (b) CO (c) O2 (d) CO2

Choose the appropriate answers for the following questions.Whom do you often write letters to? A) To England B) To Moscow C) My friends do D) To my pen-friend E) My pen-friend does

Pete ____ by the time the meeting starts. A) arrived B) had arrived C) will have arrived D) has arrived

Choose the appropriate answers for the following questions.Who has cut the hand? A) I did B) He has C) Pete does D) Ann had E) The knife had

Name the non metal which exists in liquid form at room temperature. a) Oxygen b) Hydrogen c) Bromine d) Mercury

Indicate the number of unpaired electrons in: a. `P, b. Si, c. Cr`, d. `Fe, e. Kr`

Name the metal which can be cut with knife. a) Sodium b) Sulphur c) Iron d) Zinc

Which of the following is not a preservative? a) Sodium meta bisulphate b) Sodium chloride c) Sodium benzoate d) Sodium Carbonate

The ratio of longest and shortest wavelenghths of lyman series is

How many hybrid orbitals can form from one 1s orbital and two 2p orbitals?

Find the equation of the radical axis of x2 + y2 – 2x – 4y – 1= 0, x2 + y2 – 4x – 6y + 5 = 0.

Find the product of lengths of the perpendiculars from any point on the hyperbola x2/16 - y2/9 = 1 to its asymptotes.

A double ordinate of the curve y2 = 4ax is of length 8a prove that the lines from the vertex to its ends are at right angles.

All of the angles of a quadrilateral are congruent. Can the quadrilateral be a parallelogram?

What name is given to carbon reduction process for extracting the metal?

A spherical mirror produces an image of magnification -1 on a screen placed at a distance of 50 cm from the mirror i) write the type of mirror usedii) find the distance of the image from the imageiii) what is the focal length of the mirror

When is electrolytic reduction applied for getting a metal?

The essential component of a toaster is an electrical element (a resistor) that converts electrical energy to heat energy. How much current is drawn by a toaster with resistance 12Ω at 110V?

An electrical iron carrying 2A at 120V. Find resistance of the device?

Name the method of metal refining which is generally used when a metal of high degree of purity is needed.

A voltage source of 20Sinπt V is connected across a 5KΩ resistor. Find the current through the resistor and power dissipated.

Give reasons for the following: (a) Transition elements and their compounds act as catalysts. (b) Eo value for (Mn2+|Mn) is negative whereas for (Cu2+| Cu) + is positive. (c) Actinoids show irregularities in their electronic configuration.

What is the basic structural difference between glucose and fructose?

Write the products obtained after hydrolysis of lactose

The molecular formula of an ester is C3 H7 COOC2 H5. Write the molecular formula of the alcohol and the acid from which it might be prepared.

compound most reactive towards SN1 reaction

A voltage signal source of constant amplitude with frequency varying from dc to 25 kHz is applied to a low-pass filter. Which frequency will develop greatest voltage across the output load resistance? (a) d.c. (b) 10 kHz (c) 15 kl (d) 25 kHz

A network which attenuate a single band of frequencies and allows those on either side to pass through is called ........ filter.(a) low-pass (b) high-pass (c) band stop (d) band pass

The decibel is a measure of (a) power (b) voltage (c) current (d) power level

The frequency corresponding to half-power point on the response curve of a filter is known as — (a) cutoff (b) upper (c) lower (d) roll-off

In a simple low-pass RC filter, attenuation is – 3 dB at fc. At 2 fc , attenuation is – 6 dB. At 10 f c, the attenuation would be .... dB. (a) – 30 (b) – 20 (c) – 18 (d) – 12

In an RL low-pass filter, an attenuation of – 12 dB/octave corresponds to ........... dB/ decade. (a) – 6 (b) – 12 (c) – 20 (d) – 40

In a simple high-pass RC filter, if the value of capacitance is doubled, the cutoff frequency is (a) doubled (b) halved (c) tripled (d) quadrupled

When two simple low-pass filters having same values of R and C are cascaded, the combined filter will have a roll-off of ...... dB/decade. (a) – 20 (b) – 12 (c) – 40 (d) – 36

An a.c. signal of constant voltage 10 V and variable frequency is applied to a simple high-pass RC filter. The output voltage at ten times the cutoff frequency would be ............... volt. (a) 1 (b) 5 (c) 10/√2 (d) 10√2

In a simple high-pass RL filter circuit, the phase difference between the output and input voltages at the cutoff frequency is .... degrees. (a) – 90 (b) 45 (c) – 45 (d) 90