This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
The study of motion, mechanics and energy is part of ___ |
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Answer» Correct answer is Physics |
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| 2. |
The study of land forms and population growths are included in ___ |
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Answer» Correct answer is Geography |
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| 3. |
The study of the periodic table, gasses, liquids, acids and alkalis is called ___ |
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Answer» Correct answer is Chemistry |
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| 4. |
Column I Column II (a) Eosinophils(i)Coagulation(b) RBC(ii)Universal Recipient(c) AB Group(iii)Resist Infections(d) Platelets(iv)Contraction of Heart(e) Systole(v)Gas transport |
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| 5. |
Which β−keto acid shown will not undergo decarboxylation ? |
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Answer» The correct option is (B). α β−keto acid having it's α carbon at bridged head can't under go tautomerisation and it has a fixed hybridisation of sp3. ⇒ can't undergo decarboxylation. |
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| 6. |
During the process of nutrition, the first step is the break-down of glucose into a pyruvate in the cytoplasm. Further, the pyruvate may be converted into ethanol and CO2 (anaerobic respiration). Breakdown of pyruvate into 3- molecules of CO2 using oxygen (aerobic respiration) releases a lot greater energy than in the anaerobic process. When there is a lack of oxygen, pyruvate is converted into lactic acid. ATP, after the energy released during cellular respiration, is synthesised and it drives the endothermic reactions taking place in the cell. I. ATP molecule is made from a) ADP b) IADP c) GADP d) Nucleotide with 3 phosphates II. Energy equivalent to ......... is released when an ATP molecule is broken a) 15 kJ/mol b) 30 kJ/mol c) 45 kJ/mol d) 65 kJ/mol III. How many carbons are there in a pyruvate molecule? a) 6 b) 5 c) 4 d) 3 IV. An example of micro-organism where pyruvate is converted into C2H5OH and CO2 during fermentation is: a) Bacteria b) Algae c) Yeast d) None V. Breakdown of pyruvate into CO2 using oxygen takes place in: a) Golgi bodies b) Mitochondria c) Centrosomes d) None |
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Answer» (i) (d) (ii) (b) (iii) (d) (iv) (c) (v) (b) |
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| 7. |
Name the organic materials the exine and intine of an angiosperm pollen grain are made up of. Explain the role of exine. |
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| 8. |
Why is it considered that the presence or absence of hymen is not an indication of virginity? |
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| 9. |
A coolbox in the shape of a cube is used to keep beverages cool, with each sidemeasuring 45 cm. Its walls are 3 cm thick and made of plastic(kplastic = 0.03 W.m-1.°C-1). Determine the heat flux through the walls of the coolbox ifthe difference between the outside and inside temperature is 20°C. |
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Answer» \(H=mL \) ∵ H = KA \((\frac{△t}{△x})t\) KA \((\frac{△t}{△x})+=ML \) 0.03 × 6 × (0.45)2 × \((\frac{20}{0.03})×3600=M×80×4.2×1000\) \(M=\frac{87480}{336000} \) \(M=0.26kg \) |
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| 10. |
two sample of gas at same temperature and pressure air compressed v to v/2 one sample isothermal and other adiabatically |
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Answer» Let two gas of sample is A and B then pressure of A is less than that of B |
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| 11. |
The pressure at a point in water column is 3.924 N/cm2 . What is the corresponding height of water? (a) 8 m (b) 6 m (c) 4 m (d) 2 m |
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Answer» (c) 4 m Pressure in water column of height ‘h’. P = \(\rho\)gh 3.924 × 104 = 103 × 9.81h \(\therefore\) h = \(\frac{39.24}{9.81}\) = 4m |
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| 12. |
Which one of the following methods can be adopted to obtain isothermal compression in an air compressor? (a) Increasing the weight of the compressor (b) Interstage heating (c) Atmospheric cooling (d) Providing appropriate dimensions to the cylinder |
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Answer» (c) Atmospheric cooling In reciprocating engine to achieve high pressure ratio the condition of minimum work is required which is possible in isothermal compression. To do isothermal compression intercooler is installed in between stages of compressor at outside of cylinder since intake is at atmospheric in general (except aircraft and all), so, temperature is at inlet is atmospheric. Since, process is isothermal so, intercooling will be isothermal atmospheric intercooling (the above is for ideal case not for real). By providing appropiate dimension to cylinder we can increase volumetric efficiency not achieve the isothermal cooling. |
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| 13. |
Area of a quadrilateral whose sides and one diagonal are given, can be calculated by dividing the quadrilateral into .............. triangles and using the ............... formula. (a) two, semi-area (b) three, Heron's (c) four, Heron's (d) two, Heron's |
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Answer» (d) Area of the quadrilateral whose side and one diagonal are given can be calculated by dividing the quadrilateral into two triangles and using the Heron's formula. |
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| 14. |
White and grey coloured triangular plastic sheets are used to make a toy as shown in figure. Find the difference in areas of shaded and unshaded coloured sheets used for making the toy.(a) 1 cm2 (b) 0 cm2 (c) 5√2 cm2 (d) 16√2 cm2 |
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Answer» (b) Sides of white coloured triangular plastic sheet are 4 cm, 6 cm and 6 cm but sides of grey coloured triangular sheet are also 4 cm, 6 cm and 6 cm. It is clear they must have equal areas. Hence, difference in areas of shaded and unshaded colour sheets is (zero) 0 cm2. |
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| 15. |
In a family with two sons, a father has a field in the form of a right angled triangle with sides including right angle are 18 m and 40 m. He wants to give independent charge to his sons, so he divided the field in the ratio 2 : 1 : 1, the bigger part he kept for himself and divided remaining equally among the sons, find the total area distributed to the sons. (a) 360 m2 (b) 90 m2 (c) 180 m2 (d) 200 m2 |
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Answer» (c) Area of the field 1/2 (18 x 40) = 360 m2 Father divided the field in the ratio 2 : 1 : 1 by keeping bigger part for himself. He devided it into two equal parts. One part he kept for himself and other part he further divided between the sons. Total area distributed to the sons = 360 ÷ 2 = 180 m2 |
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| 16. |
We have a fixed conductor having a cavity inside. There is a point charge `q_(1)` kept inside the cavity charge appearing at the inner surface of the cavity is `q_(2)`. Charge appearing at outer surface of conductor is `q_(3)` and there lies another point charge `q_(4)` out side the conductor. Whole situation is shown in figure. `q_(4)`. is held stationary by applying an external force `vecF_(0)` on it. Three points A, B and C are shown. Answer the following two questions. Q. If keeping the magnitude and nature of `q_(1)` fixed position of `q_(1)` is changed inside the cavity. Then choose the correct option(s)A. External force required to keep `q_(4)` stationary remains unchangedB. intensity of electric field at point C remains unchangedC. intensity of electric field at point B remains unchangedD. intensity of electric filed point B only due to `q_(2)` remains unchanged. |
| Answer» Correct Answer - A::B::C | |
| 17. |
We have a fixed conductor having a cavity inside. There is a point charge `q_(1)` kept inside the cavity charge appearing at the inner surface of the cavity is `q_(2)`. Charge appearing at outer surface of conductor is `q_(3)` and there lies another point charge `q_(4)` out side the conductor. Whole situation is shown in figure. `q_(4)`. is held stationary by applying an external force `vecF_(0)` on it. Three points A, B and C are shown. Answer the following two questions. Q. If keeping the nature and position of `q_(1)` fixed, magnitude of `q_(1)` is changed, then choose the INCORRECT options(s)A. External force required to keep `q_(4)` stationary remains unchangedB. intensity of electric field at point C remains unchangedC. intensity of electric field at point B remains unchangedD. intensity of electric filed point B only due to `q_(2)` remains unchanged. |
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Answer» Correct Answer - A::B::D Answers are obvious using properties of conductor. |
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| 18. |
Figure shows a conducting sphere with a cavity. A point charge `q_(1)` is placed inside cavity, and `q_(2)` is placed out side the sphere `vec(E)_("in")` is electric field due to charge induced on surface of cavity. `vec(E)_("out")` is electric field due to charge induced on outer surface of sphere and `vec(E)_("net")` is net field at any point. Two closed gaussian surface `S_(1)` & `S_(2)` are also drawn in the figure. A. `int vec(E)_("net").vec(d)a` for surface `S_(1)` is zeroB. `intvec(E)_("net").vec(d)a` for surface `S_(2)` is `(q_(1)+q_(2))/(epsilon_(0))`C. `int vec(E)_("in").vec(d)a` for surface `S_(1)` is `(-q_(1))/(epsilon_(0))`D. `int vec(E)_("out").vec(d)a` for surface `S_(2)` is `(q_(1))/(epsilon_(0))` |
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Answer» Correct Answer - A::B::C::D Charge induced on inner surface of cavity `-q_(1)` Charge induced on outer surface of sphere `=q_(1)` Net charge enclosed by `S_(1)` is zero Net charge enclosed by `S_(2)` in `q_(1)+q_(2)` |
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| 19. |
Figure shows a conducting sphere with a cavity. A point charge `q_(1)` is placed inside cavity, and `q_(2)` is placed out side the sphere `vec(E)_("in")` is electric field due to charge induced on surface of cavity. `vec(E)_("out")` is electric field due to charge induced on outer surface of sphere and `vec(E)_("net")` is net field at any point. Two closed gaussian surface `S_(1)` & `S_(2)` are also drawn in the figure. A. `int vec(E)_("net").vec(d)a` for surface `S_(1)` is zeroB. `intvec(E)_("net").vec(d)a` for surface `S_(2)` is `(q_(1)+q_(2))/(epsilon_(0))`C. `int vec(E)_("in").vec(d)a` for surface `S_(1)` is `(-q_(1))/(epsilon_(0))`D. `int vec(E)_("out").vec(d)a` for surface `S_(2)` is `(q_(1))/(epsilon_(0))` |
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Answer» Correct Answer - A::B::C::D Charge induced on inner surface of cavity `-q_(1)` Charge induced on outer surface of sphere `=q_(1)` Net charge enclosed by `S_(1)` is zero Net charge enclosed by `S_(2)` in `q_(1)+q_(2)` |
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| 20. |
There is a cubical cavity inside a conducting sphere of radius R. A positive point charge Q is placed at the centre of the cube and another positive charge q is placed at a distance `1(gtR)` from the centre of the sphere. The sphere is earthed Net charge on the outer surface of conducting sphere isA. `+Q`B. `Q-qR//1`C. `-qR//I`D. none |
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Answer» Correct Answer - C Potential of the sphere is zero as it is earthed so potehtial at the centre, v=0 `Rightarrowv=(Kq)/l+(QE)/R=0` `Q^(1)`=charge induced on the surface of the sphere `Rightarrow Q^(1)=(-qR)/l` |
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| 21. |
(i) ` 2P^(2)+9P+9 = 0` (ii) `15Q^(2) + 16Q + 4 = 0`A. `P gt Q`B. `P lt Q`C. `P ge Q`D. ` P le Q` |
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Answer» Correct Answer - B (i) `2P^(2)+9P+9=0` `2P^(2)+(6+3)P+9=0` `2P(P+3)+3(P+3)=0` `P=(-3)/(2),-3` (ii) `15Q^(2)+16Q+4=0` `15Q^(2)+10Q+6Q+4=0` `5Q(3Q+2)(3Q+2)=0` `Q=(-2)/(5),(-2)/(3)` `PltQ` |
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| 22. |
In YDSE, let A and B be two slits. Films of thickness `t_(A)` and `t_(B)` and refractive `mu_(A)` and `mu_(B)` are placed in front of A and B, respectively. If `mu_(A) t_(A) = mu_(A) t_(B)`, then the central maxima willA. not shiftB. shift forwards AC. shift towards BD. none of these |
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Answer» Correct Answer - A::B::C The path difference `Delta X=(mu_(A)-1)t_(A)-(mu_(B)-1)t_(B)` `rArr Delta X = mu_(A)t_(A) -t_(A)-mu_(B)t_(B)+t_(B)` `rArr Delta X = t_(B) - t_(A)` If `t_(B) = t_(A)` `rArr Delta X = 0` `rArr` no shift if `t_(B)gt t_(A) or t_(B) lt t_(A)` `DeltaX ne 0` central maxima may shift towards A or B |
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| 23. |
In a double slit experiment, two parallel slits are illuminated first by light of wavelength 400 nm and then by light of unknown wavelength. The fourth order dark fringe resulting the known wavelength of light falls in the same place on the screen as the second order bright fringe from the unknown wavelength. The value of unknown wavelength of light isA. 900nmB. 700nmC. 300nmD. none of these |
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Answer» Correct Answer - B `Yn=(n+(1)/(2))(Dlamda)/(d)n=1,2,3` `(3+(1)/(2))(Dlamda_(1))/(d)=2xx(Dlamda_(2))/(d)` `lamda_(2)=(7)/(4)lamda_(1)=(7)/(4)xx400=700nm` |
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| 24. |
Two slits separated by 1 mm in Young's double slit experiment are illuminated by the violet light of the wavelength 400 nm. The interference fringes are obtained on the screen placed at 1 m from the slits. Find the fringe width. If the violet light is replaced by the red light of the wavelength 700 nm, find the percentage change in fringe width. |
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Answer» Slit separation, d = 1 mm = 1 x 10-3 m wavelength \(\lambda\) = 6.5 x 10-7 m screen distance D = 1m Distance b/w 3rd dark fringe and 5th bright fringe Dark fringe yn = \(\frac{(2n-1)\lambda D}{2d}\) Bright fringe yn = \(\frac{n\lambda D}d\) y5 - y3 = \(\frac{5\times6.5\times10^{-7}\times1}{10^{-3}}\) - \(\frac{(2\times3-1)\times6.5\times10^{-7}}{2\times10^{-3}}\) = 32.5 x 10-4 - 16.25 x 10-4 = 16.25 x 10-4 m The distance b/w the third dark fringe and fifth bright fringe is 1.625 mm. |
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| 25. |
The velocity associated with a proton moving in a potential difference of `1000 V` is `4.37xx10^(5) m s^(-1)`. If the hockey ball of mass `0.1 kg` is moving with this velocity, calculate the wavelength associated with this velocity. |
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Answer» `lambda=h/(mv)=(6.626xx10^(-34) kgm^(2) s^(-1))/((0.1 kg)xx(4.37xx10^(5) m s^(-1)))` `=1.516xx10^(-28) m` |
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| 26. |
Ethrane is used asA. a flavouring agentB. a solventC. an inhalation anaestheticD. a perfume |
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Answer» Correct Answer - C Ethrane is an inhalation anaesthetic `CI-overset(CI)overset(|)CH-underset("Ethrane")underset(F)underset(|)overset(F)overset(|)C-O-CHF_2` |
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| 27. |
Similar to electron diffraction, neutron diffraction microscope is also used for the determination of the structure of molecules. If the wavelength used here is `800 p m`, calculate the characteristic velocity associted with the neutran. |
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Answer» `lambda=h/(mv)` or `v=h/(mxxlambda)` `(6.626xx10^(-34) kgm^(2) s^(-1))/(1.675xx10^(-27)kgxx(800xx10^(-12)m))` `=4.94xx10^(4) m s^(-1)` |
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| 28. |
Anisole with conc. `H_(2)SO_(4)` gives.A. PhenolB. o-Phenol sulphonic acidC. o-and p-sulphoanisaolesD. m-sulphoanisole |
| Answer» Correct Answer - C | |
| 29. |
Which of the following compounds is not cleaved by HI even at 525 K ?A. `C_6H_5OCH_3`B. `(Ph)_(2)O`C. `C_6H_5OC_(3)H_7`D. |
| Answer» Correct Answer - B | |
| 30. |
The number of terms in an A.P. -3, 3, 9, 15,………..,201 is:1. 352. 343. 324. 33 |
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Answer» Correct Answer - Option 1 : 35 Given: The number of terms in an A.P. -3, 3, 9, 15,………..,201 Formula used: d = t2 – t1 a + (n – 1)d where, a = first term, n = last term and d = common difference Calculation: a = -3 d = 3 – (-3) ⇒ d = (3 + 3) = 6 nth term = 201 According to the question ⇒ a + (n – 1)d ⇒ -3 + (n – 1) × 6 = 201 ⇒ -3 + 6n – 6 = 201 ⇒ 6n = 210 ⇒ n = 35 ∴ Total number of term is 35 |
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| 31. |
If x = 8, y = 27, then the value of \(\left({X^{\frac{4}{3}}+y^{\frac{2}{3}}}\right)^{\frac{1}{2}}\)1. 52. 13. 24. 4 |
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Answer» Correct Answer - Option 1 : 5 Given: x = 8, y = 27 Calculation: According to the question \(\left({X^{\frac{4}{3}}+y^{\frac{2}{3}}}\right)^{\frac{1}{2}}\) ⇒ (84/3 + 272/3)1/2 ⇒ (23 × 4/3 + 33 × 2/3)1/2 ⇒ (24 + 32)1/2 ⇒ (16 + 9)1/2 ⇒ (25)1/2 ⇒ 5 ∴ Required value is 5 |
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| 32. |
Find the equations of the perpendicular from the point (3, −1, 11) to the line \(\frac{x}{2}\) = \(\frac{y-2}{3}\) = \(\frac{Z-3}{4}\) . Also, find the coordinates of the foot of the perpendicular and the length of the perpendicular. |
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Answer» Given line is \(\frac{x}{2}\) = \(\frac{y-2}{3}\) = \(\frac{z-3}{4}\) . The direction ratios of the line are 2, 3 and 4. Now, \(\frac{x}{2}\) = \(\frac{y-2}{3}\) = \(\frac{z-3}{4}\) = \(\lambda\) (Let) ⇒ x = 2\(\lambda\), = 3\(\lambda\) + 2 and = 4\(\lambda\) + 3. Hence, the points on the line \(\frac{x}{2} = \frac{y-2}{3} = \frac{z-3}{4}\) is of the form Q (2\(\lambda\), 3\(\lambda\) + 2, 4\(\lambda\) + 3). The direction ratios of the line joining points (3, −1, 11) and (2\(\lambda\), 3\(\lambda\) + 2, 4\(\lambda\) + 3) are 2\(\lambda\) − 3, 3\(\lambda\) + 2 − (−1) and 4\(\lambda\) + 3 − 11 = 2\(\lambda\) − 3, 3\(\lambda\) + 3 and 4\(\lambda\) − 8. Let the foot of the perpendicular is Q (2\(\lambda\), 3\(\lambda\) + 2, 4\(\lambda\) + 3). Let line PQ is perpendicular to the given line \(\frac{x}{2} = \frac{y-2}{3} = \frac{z-3}{4}.\) Therefore, 2(2\(\lambda\) - 3)+3(3\(\lambda\) + 3) + 4(4\(\lambda\) - 8) = 0. (Because, the sum of product of direction ratios of two perpendicular lines is equal to zero.) ⇒ 4\(\lambda\) − 6 + 9\(\lambda\) + 9 + 16\(\lambda\) − 32 = 0 ⇒ 29\(\lambda\) − 29 = 0 ⇒ \(\lambda\) = \(\frac{29}{29}= 1\). Now, putting the value of = 1 in the equation of points on the given line. Therefore, the foot of the perpendicular is Q (2\(\lambda\), 3\(\lambda\) + 2, 4\(\lambda\) + 3) = Q(2, 5, 7). The equation of line PQ is \(\frac{x-3}{2-3} = \frac{y-(-1)}{5-(-1)}\) = \(\frac{z-11}{7-11} ⇒ \frac{x-3}{-1}\) = \(\frac{y+1}{6}\) = \(\frac{z-11}{-4}\) The equation of the perpendicular from the point (3, −1, 11) to the line \(\frac{x}{2} = \frac{y-2}{3}\) = \(\frac{z-3}{4}\) is \(\frac{x-3}{-1} = \frac{y+1}{6} = \frac{z-11}{-4}\). Now, length of perpendicular is = \(\sqrt{(2-3)^2 + (5-(-1))^2+ (7-11)^2}\) = \(\sqrt{(-1)^2 + 6^2 + (-4)^2}\) = \(\sqrt{1+36+16}\) = \(\sqrt{53}\) units. |
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| 33. |
Find the direction cosines of a line that makes equal angles with the co-ordinates axes. |
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Answer» We know that the direction cosines of a line making \(\alpha\), \(\beta\) and \(\gamma\) angles with x, y and z-axes, respectively are l = cos \(\alpha\) ,m = cos \(\beta\) and n = cos \(\gamma\). Now, given that a line makes equal angles with the co-ordinates axes. i.e., \(\alpha\) = \(\beta\) = \(\gamma\). Therefore, the direction cosines of given line are l = cos \(\alpha\) , m = cos \(\alpha\) and n = cos\(\alpha\). We also know that the sum of squares of direction cosines is equal to 1. i.e., l2 + m2 + n2 = 1. Therefore, cos2 \(\alpha\) + cos2 \(\alpha\) + cos2 \(\alpha\) = 1 ⇒ 3 cos2 \(\alpha\) = 1 ⇒ cos2 \(\alpha\) = \(\frac{1}{3}\) . ⇒ cos = ± \(\frac{1}{\sqrt{3}}\). Therefore, the direction cosines of given line are l = ±\(\frac{1}{\sqrt{3}}\),m = ±\(\frac{1}{\sqrt{3}}\) and n = ±\(\frac{1}{\sqrt{3}}\). |
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| 34. |
The smallest no. that is divisible by both 306 & 657. |
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Answer» We have to find smallest number which is divisible by 306 and 657 306 = 2 × 3² × 17 657 = 3 × 3 × 73 LCM of 306 and 657 = 2 × 3² × 17 × 73 = 2 × 9 × 17 × 73 = 18 × 17 × 73 = 306 × 73 = 22338 Hence, smallest number is 22338 which is divisible by 306 and 657. |
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| 35. |
In ∆ABC, ˂B=90˚ and BD ꓕ AC. If AC = 9cm and AD = 3 cm then BD is equal to(a) 2√2 cm(b) 3√2 cm(c) 2√3 cm(d) 3√3 cm |
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Answer» Correct answer is: (b) 3√2 cm CD/BD = BD/AD BD2 = CDXAD = 6X3 BD=3√2 cm |
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| 36. |
Ram calculates his profit percentage on cost price and Amit calculates on selling price. Their selling price are same, and sum of their actual profit is Rs. 360 and both claims to have made 25% profit. What is the selling price?1. Rs. 5002. Rs. 6003. Rs. 7004. Rs. 800 |
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Answer» Correct Answer - Option 4 : Rs. 800 Given: Ram calculates profit percent on C.P and Amit calculates on S.P Profit earned by Ram + profit earned by Amit = 360 Profit percentage earned by Ram and Amit each = 25% Selling price of Ram = Selling price of Amit Formula used: % Profit = (profit/cost price) × 100 Cost price = 100/(100 + a%) × selling price Where, a% → percent profit Concept used: Profit/loss is always calculated on C.P Calculation: Let S.P of Ram and Amit be X % profit earned by Ram = 25% C.P of Ram = 100/(100 + 25) × X ⇒ (100/125) × X ⇒ 4/5 × X ⇒ 4X/5 Ram calculates his profit percent on C.P Profit earned by Ram = 25% of C.P ⇒ 25% of 4X/5 = X/5 ----(1) Similarly, S.P of Amit = X Amit calculates his profit percent on S.P Profit earned by Amit = 25% of X ⇒ (25/100) × X = X/4 ----(2) Profit earned by Ram + profit earned by Amit = 360 ⇒ X/5 + X/4 = 360 ⇒ (4X + 5X)/20 = 360 ⇒ 9X = 360 × 20 ⇒ X = 7200/9 ⇒ X = 800 ∴ The selling price of each is Rs. 800. |
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| 37. |
Dinesh calculates his profit percentage on the cost price whereas Mahesh calculates his profit percentage on the selling price. They find that the difference in their profits is Rs. 200. If the selling price of both of them are the same and both of them get 20% profit, find their selling price.1. 80002. 70003. 40004. 60005. None of these |
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Answer» Correct Answer - Option 4 : 6000 Given: Difference between their profits = 200 Profit gain by Mahesh and Dinesh both = 20% Formula used: Gain or loss percent = (Loss or gain/Cost price) × 100 Concept used: Profit = Selling Price – Cost Price Loss = Cost Price – Selling Price Calculation: Let the selling price for both of them be Rs. x. Cost price of Dinesh = x × {(100 - 20)/100} ⇒ x × {80/100} ⇒ 4x/5 Cost price of Mahesh = x × {100/(100 +20)} ⇒ x × {100/120} ⇒ 5x/6 Dinesh’s profit = x – (4x/5) ⇒ x/5 Mahesh’s profit = x – (5x/6) ⇒ x/6 Difference of their profits = (x/5) – (x/6) = 200 ⇒ x/30 = 200 ⇒ x = 6000 ∴ The selling price for both of them is Rs. 6000. |
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| 38. |
Three successive discounts 22%, 17% and 11% are equivalent to a single discount of:1. approximately 50%2. approximately 42%3. approximately 45%4. approximately 25% |
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Answer» Correct Answer - Option 2 : approximately 42% Given: Discount 1 percent = 22% Discount 2 percent = 17% Discount 3 percent = 11% Calculation: Let the initial price be 100 Discount 1 = 22% of 100 Discount 1 = 22 Price after discount 1 = 100 – 22 = 78 Discount 2 = 17% of 78 Discount 2 = 13.26 Price after discount 2 = 78 – 13.26 = 64.74 Discount 3 = 11% of 64.74 Discount 3 = 7.1214 Price after discount 3 = 64.74 – 7.1214 Final price after third discount = 57.6186 Total discount = Initial price – Final price = 100 – 57.6186 = 42.3814 Total discount ≈ 42 Discount% ≈ (Total discount/Initial price) × 100 ⇒ Discount% ≈ (42/100) × 100 ⇒ 42% ∴ Discount percentage is approximately 42% |
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| 39. |
A man sold two articles for Rs. a each. On one he gains b% and on the other he losses b%, then his percentage of loss is |
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Answer» Correct Answer - Option 3 : \({\left( {\frac{b}{{10}}} \right)^2}\) Given: The selling price of each article = Rs. a Gain on one article = b% Loss on another article = b% Concept used: Where there is a profit of x% and loss of y% in a transaction then the resultant profit or loss per cent is given by [x - y - xy/100] Calculations: Here x = y = b (b - b - b × b/100) = -b2/100 ⇒ -(b/10)2 -ve sign means loss occurred ∴ The loss is (b/10)2 |
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| 40. |
A diatomic gas `(gamma=1.4)` does 2000J of work when it is expanded isobarically. Find the heat given to the gas in the above process (in kJ).A. 7000B. 7C. 5000D. 5 |
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Answer» Correct Answer - B For a diatomic gas, `C_(v)=(5)/(2)R` and `C_(v)=(7)/(2)R` The work done is an isobaric procers is `W=p(V_(2)-V_(1))=nRT_(2)-nRT_(1)` or `T_(2)-T_(1)=(W)/(nR)` The heat given in an isobaric process is `Q=nC_(p)` `(T_(2)-T_(1))=nC_(p)(W)/(nR)=(7)/(2)` `W=(7)/(2)xx2000J=7000J=7kJ` |
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| 41. |
If y = f(x) = x2 + x, x = 10, ∆x = 0.1, find ∆y, dy. |
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Answer» Given y = x2 + x, x = 10 and ∆x = 0.1 ∆y = f(x + ∆x) – f(x) = (x + ∆x)2 + (x + ∆x) – (x2 + x) = x2 + 2x ∆x + (∆x)2 + x + ∆x – x2 – x = 2x ∆X + (∆x)2 + ∆x = 2(10) (0.1) + (0.1)2 + 0.1 = 2 + 0.01 + 0.1 = 2.11 dy = f1 (x) ∆x = (2x + 1) ∆x = {2.(10) + 1} (0.1) = (21) (0.1) = 2.10. |
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| 42. |
Which of the following is not the unit of energy ?A. calorieB. jouleC. electron voltD. watt |
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Answer» Correct Answer - D watt is a unit of power |
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| 43. |
The equilibrium constant `(K_(p))` for the decomposition of gaseous `H_(2)O` `H_(2)O(g)hArr H_(2)(g)+(1)/(2)O_(2)(g)` is related to the degree of dissociation `alpha` at a total pressure P byA. `K_(p)=(alpha^(3)P^(1//3))/((1+alpha)(2+alpha)^(1//2))`B. `K_(p)=(alpha^(3)P^(3//2))/((1-alpha)(2+alpha)^(1//2))`C. `K_(p)=(alpha^(3//2)P^(3))/((1-alpha)(2+alpha)^(1//2))`D. `K_(p)=(alpha^(3//2)P^(1//2))/((1-alpha)(2+alpha)^(1//2))` |
| Answer» Correct Answer - D | |
| 44. |
If a photon with `12`eV energy is incidented on hydrogen atom then what will be true statement from the following `:-`A. Electron will transfer in first excited state and its energy will be increased by `1.8` eVB. In atom electron will remain in ground state bur its total energy will be `-` `1.6` eVC. Atom will not absorb the photon.D. None of these |
| Answer» Correct Answer - C | |
| 45. |
What will be the number of spectral lines in infrared region when electron transition occur from `n=7` to `n=2` in hydrogen atom `:-`A. `5`B. `10`C. `15`D. Zero |
| Answer» Correct Answer - B | |
| 46. |
A point charge of `0.009 mu C` is placed at origin. Calculate intensity of electric field due to this point charge at point `(sqrt(2), sqrt(7), 0)`. |
| Answer» `vec(E)=(qvec(r))/(4pi in_(0)r^(3))`, where `vec(r)=xhat(i)+yhat(j)=sqrt(2)hat(i)+sqrt(7)hat(j), vec(E)=(9xx10^(5)xx9xx10^(-9)(sqrt(2)hat(i)+sqrt(7)hat(j)))/((3)^(3))=(3sqrt(2)hat(i)+3sqrt(7)hat(j))NC^(-1)` | |
| 47. |
A charge `2 mu C` is taken from infinity to a point in an electric field, without changing its velocity, if work done against electrostatic forces is `-40 mu J` then potential at that poin is? |
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Answer» `V=W_("ext")/(q)=(-40 muJ)/(2 mu C)=-20 V` Note : Always remember to put sign of W and q. |
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| 48. |
If the dimensions of a physical quantity are given by `M^(x) L^(y) T^(z)`, then physical quantity may beA. acceleration due to gravity, if `x=0, y=1, z=-2`B. atmospheric pressure, if `x=1, y=1, z=-2`C. linear momentum, if `x=1, y=1, z=-1`D. potential energy, if `x=1, y=2, z=-2` |
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Answer» Correct Answer - A::C::D For (A) : `["Acceleration"]=[LT^(-2)]` For (B) : `["Energy"]=[ML^(2)T^(-2)]` for (C) : `["Momentum"]=[MLT^(-1)]` For (D) : `["Energy"]=[ML^(2)T^(-2)]` |
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| 49. |
The dimensional formula of angular velocity isA. `M^(@)L^(@)T^(-1)`B. `MLT^(-1)`C. `M^(@)L^(@)T^(1)`D. `ML^(@)T^(-2)` |
| Answer» `omega=(Deltatheta)/(Deltat)=("angle")/("time")=M^(0)L^(0)T^(-1)` | |
| 50. |
If A and B are two physical quantities having different dimensions then which of the following can denote a new physical quantity?A. `A+(A^(3))/(B)`B. `exp(-(A)/(B))`C. `AB^(2)`D. `(A)/(B^(4))` |
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Answer» For (A): A and `(A^(3))/(B)` may have same dimension. For (B) : As A and B have different dimension so `exp(-(A)/(B))` is meaningless. For (C): `AB^(2)` is meaningful, For (D) : `AB^(-4)` is meaningful. |
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