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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. |
A block of mass M is kept in elevator (lift) which starts moving upward with constant acceleration b as shown in figure. Initially elevator at rest. The block is observed by two observers A and B for a time interval `t=0` to `t=T`. Observer B is at rest with respect to elevator and observer A is standing on the ground. Q. The observer A finds that work done by normal reaction acting on the blocks isA. `(1)/(2)M(g+b)^(2)T^(2)`B. `-(1)/(2)M(g+b)^(2)T^(2)`C. `(1)/(2)M(g+b)bT^(2)`D. `(1)/(2)M(g+b)bT^(2)` |
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Answer» Correct Answer - C The normal reaction acting on the block is `M(g+b)` in upward direction. The upward displacement of the block is `(1)/(2)bT^(2)` hence the work done by normal reaction is `M(g+b)xx(1)/(2)bT^(2)` |
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| 2. |
The displacemennt of a moving partical is proportional to the square of the time, For this particleA. the velocity is constantB. the velocity is variableC. the acceleration is constantD. the acceleration is variable |
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Answer» Correct Answer - B::C `s prop t^(2)` `:. s = ct` where `c = constant` `(i) v = (ds)/(dt) = 2 ct` `:. V prop t` `(ii) a = (dv)/(dt) = 2c` so, `a = constant` |
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| 3. |
And I need full answer please....As soon as possible... because my child is going to have a test ..... |
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Answer» 1 Kilogram : The kilogram (abbreviation, kg) is the Standard International (SI) System of Units unit of mass. 1 Kilogram is defined as the mass of one liter (10-3 cubic meter) of pure water. 1 Quintal = 100 kg and 100 kg = 1 quintal. hence 1 kg = 1/100 = 0.01 quintal 1 kg = 0.001 metric ton 1 kg = 1000 gram |
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| 4. |
One end of a light string of length `L` is connected to a ball and the other end is connected to a fixed point `O`. The ball is released from rest at `t = 0` with string horizontal and just taut. The ball then moves in vertical circular path as shown. The time taken by ball to go from position `A` to `B` is `t_(1)` and from `B` to lowest position `C` is `t_(2)`. Let the velocity of ball at `B` is `vec v_(B)` and at `C` is `vec v_(C)` respectively. If `|vec v_(C)=2|vecv_(B)|` then the value of `theta` as shown isA. `cos^(-1)((1)/(4))`B. `sin^(-1)((1)/(4))`C. `cos^(-1)((1)/(2))`D. `sin^(-1)((1)/(2))` |
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Answer» Correct Answer - B `v_(B)=sqrt(2gLsintheta)` and `v_(C)=sqrt(2gL)` if `V_(C)=2v_(B)` Then `2gL=4(2gLsintheta)` or `sintheta(1)/(4)orthetasin^(-1)((1)/(4))` |
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| 5. |
A bomber plane moving at a horizontal speed of `20 m//s` releases a bomb at a height of `80 m` above ground as shown. At the same instant a Hunter of negligible height starts running from a point below it, to catch the bomb with speed `10 m//s`. After two seconds he relized that he cannot make it, he stops running and immediately hold his gun and fires in such direction so that just before bomb hits the ground, bullet will hit it. What should be the firing speed of bullet (Take `g = 10 m//s^(2)`) A. `10 m//s`B. `20sqrt(10)m//s`C. `10sqrt(10)m//s`D. None of these |
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Answer» Correct Answer - C In `2` sec. horizontal distance travelled by bomb `= 20 xx 2 = 40 m` In `2` sec. vertical distance travelled by bomb `= (1)/(2) xx 10 xx 2^(2) = 20 m` In `2` sec. horizontal distance travlled by Hunter `= 10 xx 2 = 20 m` Time remaining for bomb to hit ground `= sqrt((2 xx 80)/(10)) - 2 = 2 sec`. Let `V_(x)` and `V_(y)` be the velocity components of bullet along horizontal and vertical direction. Thus we use, `(2V_(y))/(g) = 2` `rArr V_(Y) = 10 m//s` and `(20)/(V_(x) - 20) = 2 rArr V_(x) = 30 m//s` Thus velocity of firing is `V = sqrt(V_(x)^(2) + V_(y)^(2)) = 10sqrt(10) m//s`. |
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| 6. |
The minimum work done required to accelerate a truck on a horizontal road from rest to speed `v`A. is less than that required to accelerate if from `v` to `2v`.B. is equal than that required to accelerate it from `v` to `2v`.C. is more than that required to accelerate it from `v` to `2v`.D. may be any one of the above since it depends on the force acting on the truck and the distance over which it acts. |
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Answer» Correct Answer - A (Easy) Minimum work done to accelerate the truck from speed 0 to v and from v to 2v are `Delta W_(1) =(1)/(2)mv_(2)-(1)/(2)m(0)_(2)=(1)/(2)mv_(2)` and `Delta W_(2) = (1)/(2) m(2v)_(2)-(1)/(2) m(v)_(2) = (3)/(2) mv_(2)` `:. Delta W_(1) lt Delta W_(2)` |
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| 7. |
A particle is moving along straight line whose position `x` at time `t` is described by `x = t^(3) - t^(2)` where `x` is in meters and `t`is in seconds . Then the average acceleration from `t = 2` sec. to `t = 4` sec, is :A. `16 m//s^(2)`B. `18 m//s^(2)`C. `22 m//s^(2)`D. `10 m//s^(2)` |
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Answer» Correct Answer - A `v = (dx)/(dt) = 3t^(2) - 2t` |
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| 8. |
Position-time graph for a particle moving along `x-` direction is as shown in the figure. Average speed of the particle from `t = 0` to `t = 4` is : A. `(15)/(4)m//s`B. `(10)/(3)m//s`C. `(5)/(2)m//s`D. `(5)/(4)m//s` |
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Answer» Correct Answer - A `ltspeedgt = (5 + 10)/(4) = (15)/(4)m//s`. |
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| 9. |
Define modulus of elasticity. |
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Answer» Modulus of elasticity is defined as the ratio of stress acting on the body to the resulting strain in it. |
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| 10. |
A paricle is projected from a point with initial speed of `10 m//sec` at an angle of `37^(@)` with the horizontal. At the same instant a fly starts on the same path of particle with constant speed of `10 m//s` Then :A. time taken by fly to complete whole path is less then time taken by particleB. acceleration of fly is zeroC. average velocity of both are same for whole journeyD. None of these |
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Answer» Correct Answer - A `t = (distance)/(speed)` Since, speed of fly `ge` speed of particle so time taken by fly is less. |
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| 11. |
Fill in the blanksR – Radius of earth, g – Acceleration due to gravity h – Height from surface of earth, d – Depth from surface of earthThe value of g at a height is(a) g(n) = ......The value of g decreases with height(b) .......\(g_d = g(1\frac{d}{R})\)(c) ........on the surfaceg = \(\frac{GM}{R^2}\)(d) ...... |
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Answer» a) g(h) = g(1 – \(\frac{2h}{R}\)) b) Variation of g with depth c) g Decreases with depth d) (Change with radius (polar, equitorial org is maximum on the earth’s surface) |
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| 12. |
Give one example for elastomers. |
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Answer» one example for elastomers is Rubber |
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| 13. |
Two cells of emf `epsilon_(1)` and `epsilon_(2)(epsilon_(2) lt epsilon_(1))` are joined as shown in figure : When a potentiometer is connected between X and Y it balances for 300 cm length against `epsilon_(0)`. On conntecting the same potentiometer between X and Z it balances for 100 cm length against `epsilon_(1)` and `epsilon_(2)`. Then the ratio `(epsilon_(2))/(epsilon_(1))` is :A. `(1)/(3)`B. `(3)/(4)`C. `(1)/(4)`D. `(2)/(3)` |
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Answer» Correct Answer - D `epsilon_(1)=300 alpha`....(i) `-epsilon_(2)+epsilon_(1)=100 alpha` ....(ii) where `alpha` is the potential gradient `:. (epsilon_(2))/(epsilon_(1))=(2)/(3)` |
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| 14. |
What is solder? |
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Answer» Solder is an alloy of lead and tin mixed in different proposition as per the work to be done. In some cases certain % of bismuth and cadmium is also added to decrease the melting point of the solder. Antimony increases the melting point of the solder. Bismuth has a special quality in comparing to most of other metals. That is it expands when it cools. This property helps to shrink the solder and there by it allows the joint become firm. The quality of the solder depends on the % of tin in the solder. To get stronger joint add more tin in the solder. For electrical work fine solder of 1½ part tin and 1 part lead is used and for sheet metal works soft solder of 1 part tin and 1 part lead is used. |
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| 15. |
What is the difference between resistor, rheostat and potential divider? |
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Answer» Resistor: a fixed resistance connected permanently in the circuit for limiting the current to definite value is called the resistor. Rheostat: a variable resistance by sliding contacts on it the current can be varied is called rheostat. Potential divider: when a resistance is used to develop a voltage drop it is called a potential divider. |
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| 16. |
What is the efficiency of the system, if the actual work output from the process is 20 J and work output for a reversible process is 25 J?(a) 10%(b) 20%(c) 40%(d) 80% |
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Answer» The correct option is (d) 80% Explanation: Efficiency = 20/25*100 = 80%. |
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| 17. |
What is the efficiency of a heat engine with heat input 20 J and work output 5 J?(a) 25%(b) 50%(c) 75%(d) 100% |
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Answer» Right answer is (a) 25% The explanation: Efficiency = 5/20*100 = 25%. |
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| 18. |
What is the coefficient of performance of a system, if its work input is 50 J and heat removed is 35 J?(a) 35%(b) 50%(c) 70%(d) 95% |
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Answer» Correct answer is (c) 70% Easy explanation: Coefficient of performance = 35/50*100 = 70%. |
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| 19. |
What is the efficiency of a heat engine with heat input 10 J and work output 7 J?(a) 30%(b) 70%(c) 100%(d) 140% |
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Answer» Right option is (b) 70% For explanation: Efficiency = 7/10*100 = 70%. |
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| 20. |
Assertion (A) : If a metallic medium is placed between two charges, then electric force between them becomes zero.Reason(R) : Fm = \(\frac{F_a}{k}\)(a) Both A and R are true and R is the correct explanation of A (b) Both A and R are true but R is NOT the correct explanation of A (c) A is true but R is false (d) A is false and R is also false |
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Answer» Option : (A) For metals, Dielectric constant, K = ∞. Therefore, From Fm = \(\frac{F_a}{k}\), Electric force in medium becomes zero. |
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| 21. |
What is the efficiency of a heat engine with heat input 5 J and work output 8 J?(a) 40%(b) 80%(c) 160%(d) 200% |
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Answer» Correct answer is (c) 160% Easy explanation: Efficiency = 5/8*100 = 160%. |
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| 22. |
Assertion (A) : The temperature dependence of resistance is usually given as: R = R0(1+αΔT).The resistance of a wire changes from 100Ω to 150Ω, when its temperature is increased form 27℃ to 227℃. This implies that α = 2.5 × 10−3℃−1.Reason(R) : R = R0(1+αΔT) is valid only when the change in temperature ΔT is small and ΔR = (R − R0 ) << R0.(a) Both A and R are true and R is the correct explanation of A (b) Both A and R are true but R is NOT the correct explanation of A (c) A is true but R is false (d) A is false and R is also false |
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Answer» Option : (C) Given that, R –R0 = R0∝ ∆ 150-100 = 100×∝× (227 − 27) ∴ \(\frac{50}{100}\) =∝× 200 Or, ∝ = 2.5 × 10−3℃−1 Therefore, Assertion is true. Reason is false as R – R0 = 150 – 100 = 50Ω, Which is not much-much less than R0 (= 100Ω). |
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| 23. |
What is the efficiency of the system, if the actual work output from the process is 15 J and work output for a reversible process is 20 J?(a) 25%(b) 50%(c) 75%(d) 100% |
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Answer» Right option is (c) 75% To explain: Efficiency = 15/20*100 = 75%. |
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| 24. |
Assertion (A) : Potentiometer is more sensitive than the voltmeter. Reason(R) : Potentiometer does not draw current from the voltage source.(a) Both A and R are true and R is the correct explanation of A (b) Both A and R are true but R is NOT the correct explanation of A (c) A is true but R is false (d) A is false and R is also false |
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Answer» Option : (A) Both A and R are true and R is the correct explanation of A |
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| 25. |
Using X-ray crystallography, this woman scientist determined the structures of large biochemical molecules, including penicillin in 1949 and vitamin B12 in 1956. In 1969 she determined the three dimensional structure of insulin. In 1964 she was awarded the Nobel Prize in chemistry "for her determination by X-ray techniques of the structures of important biochemical substances." Name this woman scientist. |
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Answer» (DOROTHY) CROWFOOT HODGKIN |
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| 26. |
If the polarising angle for a given medium is 60°, then the refractive index of the medium is(A) \(\frac{1}{\sqrt{3}}\)(B) \(\sqrt{\frac{3}{2}}\)(C) 1(D) \({\sqrt{3}}\) |
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Answer» Answer is (D) 1 |
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| 27. |
The resolving power of a telescope depends upon the(A) length of the telescope (B) focal length of an objective (C) diameter of an objective (D) focal length of an eyepiece |
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Answer» (C) diameter of an objective |
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| 28. |
Electric intensity due to a charged sphere at a point outside the sphere decreases with(A) increase in charge on sphere (B) increase in dielectric constant (C) decrease in the distance from the centre of sphere (D) decrease in square of distance from the centre of sphere |
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Answer» (B) increase in dielectric constant |
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| 29. |
class 10 English ncertFrom glimpses of India |
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Answer» The Kodavas are a ethnolinguistic group from the region of Kodagu (Coorg) in the southern Indian state of Karnataka, who natively speak the Kodava language . They are traditionally land-owning agriculturists and patrilineal, with martial customs. |
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| 30. |
In potentiometer experiment, if l1 is the balancing length for e.m.f. of cell of internal resistance r and l2 is the balancing length for its terminal potential difference when shunted with resistance R then:(A) l1 = l2 \((\frac{R+r}{R})\)(B) l1 = l2 \((\frac{R}{R+r})\)(C) l1 = l2 \((\frac{R}{R-r})\)(D) l1 = l2 \((\frac{R-r}{R})\) |
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Answer» (A) l1 = l2 \((\frac{R+r}{R})\) |
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| 31. |
The process of superimposing a low frequency signal on a high frequency wave is _______. (A) detection (B) mixing (C) modulation (D) attenuation |
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Answer» Answer is: (C) modulation |
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| 32. |
Least count of a vernier callipers is `0.01 cm`. Using this, the diameter of a sphere is measured as `1.95 cm`. Radius of the sphere to the correct significant figure will beA. `0.98 cm`B. `0.975 cm`C. `1.0 cm`D. `1 cm` |
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Answer» Correct Answer - A `"diameter" d=2r=1.95` `r=(1.95)/(2)=0.975` `=0.98 cm` (after rounding the figure) |
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| 33. |
The energy of photon of wavelength λ is _______. (h = Planck’s constant, c = speed of light in vacuum)(A) hcλ(B) \(\frac{hλ}{c}\)(C) \(\frac{λ}{hc}\)(D) \(\frac{hc}{λ}\) |
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Answer» Answer is: (D) \(\frac{hc}{λ}\) |
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| 34. |
Which logic gate corresponds to the truth table given below?ABY001010100110(A) AND (B) NOR (C) OR (D) NAND |
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Answer» Answer is: (B) NOR |
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| 35. |
We decided (buy) a new car. (Choose the most suitable option) (a) We decided to by a new car (b) We decided bought a new car (c) We decided we will buy a new car (d) We decided buy a new car. |
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Answer» (a) We decided to by a new ca |
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| 36. |
A journey with him was a lesson in natural courtesy and good manners. |
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Answer» A journey with that Noble conductor was a lesson in natural courtesy and good manners. If bad manners are infectious, so also our good manners. An uncivilized fellow leaves his imprint on us and we are likely to be rude. So, most people would sympathise with the lift-man. |
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| 37. |
'The Soldier' is a/an........(a) elegy(b) ballad(c) Sonnet(d) epic |
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Answer» 'The Soldier' is a/an Sonner. |
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| 38. |
Choose the suitable meaning for the phrase: 'a big draw'.(a) a keen contest(b) A huge attraction(c) A lovely spectacle(d) A game without any result |
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Answer» (b) A huge attraction |
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| 39. |
'Good Manners' is written by......(a) C.E.M. Joad(b) J.C. Hill(c) A.G. Gardiner(d) R. Rynd |
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Answer» 'Good Manners' is written by J.C. Hill. |
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| 40. |
Why is David sent to Salem House?(a) To fetch some milk and eggs(b) To see the grandmother (c) Because he bites Mr. Murdstone's hand (d) None of these. |
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Answer» (d) None of these. |
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| 41. |
Avoid (make) silly mistake. (a) Avoid do silly mistakes. (b) Do avoid to made silly mistakes. (c) Always avoid make silly mistakes. (d) Avoid making silly mistakes. |
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Answer» (d) Avoid making silly mistakes. |
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| 42. |
The accused was guilty. He admitted this in court. (Choose the suitable combination of sentences) (a) The accused admitted in court that he was guilty. (b) The accused admit in court that he is guilty. (c) The accused admit on court that he is guilty. (d) The accused admit by court that he is guilty. |
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Answer» (a) The accused admitted in court that he was guilty. |
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| 43. |
Which of the following characters in dwarf?(a) Miss Emily(b) Miss Peggotty(c) Miss Murdstone(d) None of theses |
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Answer» (d) None of theses |
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| 44. |
The line,"And I shall have some peace there,for peace comes dropping slow",occurs in the poem.......(a) The Daffodils(b) Martha(c) Echo(d) Lake Isle of Innisfree |
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Answer» The line,"And I shall have some peace there,for peace comes dropping slow",occurs in the poem Lake Isle of Innisfree. |
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| 45. |
How did David's mother change after she married to Mr. Murdstone? |
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Answer» David mothers clara loved him heart and soul. His nurse pegotty doted on him. He was happy in his childhood but hell broke down when his mother married Mr. Murdstone who was very cruel and hard hearted. He treated David unkindly. Hence we say about David's mother change after she got married to Mr. Murdstone. |
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| 46. |
What does peggoty object to?(a) David going to school(b) Mr.Murdstone courting David's mother(c) Working late(d) Miss Betsery moving in |
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Answer» (b) Mr. Murdstone courting David's mother |
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| 47. |
David's mother gave tea to David's father in a cup.David's father told David to cool the tea as it is hot.Then David kept hot tea under the fan. What aspect did he keep in mind to cool the tea ? Explain. |
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Answer» Kishore kept in mind the concept of 'Evaporation'.Evaporation causes cooling.To make evaporation faster Kishore kept hot tea under fan. It increases the rate of evaporation and takes less time to cool the tea. |
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| 48. |
Who was David's early nurse?(a) Agnes Wickfield(b) Uriah Heep (c) Micawber(d) Clara Peggotty |
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Answer» (d) Clara Peggotty |
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| 49. |
Body of mass M is much heavier than the other body of mass m,.The heavier body with speed v collides with thelighter body which was at rest initially elastically The speed of lighter body after collisioin isA. 2VB. 3VC. VD. `V/2` |
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Answer» Correct Answer - A |
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| 50. |
A disc of mass m0 rotates freely about a fixed horizontal axis passing through its centre. A thin cotton pad is fixed to its rim, which can absorb water. The mass of water dripping onto the pad per unit time is μ. After what time will the angular velocity of the disc get reduced to half its initial value?(a) 2m0/μ (b) 3m0/μ (c) m0/μ (d) m0/2μ |
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Answer» Correct Answer is: (d) m0/2μ L = I0ω0 = Iω0/2 or 2I0 = I or 2(1/2 m0r2) = 1/2 m0r2 + (μt)r2 or t = m0/2μ |
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