InterviewSolution
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InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
A block of mass M lying on a smooth· horizontal surface is rigidly attached ·to a light horizontal ·spring of spring constant k. The other end of the spring is rigidly connected to a fixed wall. A stationary gun fires ·bullets of mass m each in horizontal direction with speed `upsilon_(0)` one after other. The bullets hit the block and get embedded to it. The first bullet hits the block at t=0, the second bullent hits at `t=2pisqrt((M+m)/(k))+2pisqrt((M+2m)/(k))` and so on. The maximum comression in the spring after the `n^(th)` bullet hits is :A. `(nm upsilon_(0)sqrt(k))/((M+nm)^(3//2))`B. `((M+nm)^(3//2))/(nm upsilon_(0)sqrt(k))`C. `(sqrt(nm upsilon_(0)k))/((M+nm)^(3//2))`D. `(nm upsilon_(0))/(sqrt(k(M+nm)))` |
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Answer» Correct Answer - D |
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| 2. |
On a smooth horizontal plane, a uniform string of mass M and length L is lying in the state of rest. A man of the same mass M is standing next to one end of the string. Now, the man starts collecting the string. Finally the man collects all the string and puts it in his pocket. What is the displacement of the man with respect to earth in the process of collection ? A. `(L)/(2)`B. `(L)/(4)`C. `(L)/(8)`D. none |
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Answer» Correct Answer - B |
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| 3. |
A man of mass M stands at one end of a stationary plank of length L, lying on a smooth surface. The man walks to the other end of the plank. If the mass of the plank is `M//3`, the distance that the man moves relative to the ground isA. `(3L)/(4)`B. `(L)/(4)`C. `(4L)/(5)`D. `(L)/(3)` |
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Answer» Correct Answer - B |
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| 4. |
At `t = 0`, the positions and velocities of two particles are as shown in the figure. They are kept on a smooth surface and being mutually attracted by gravitational force. Find the position of centre of mass at `t = 2s`. .A. X=5mB. X=7mC. X=3mD. X=2m |
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Answer» Correct Answer - B |
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| 5. |
A block of mass M is placed on the top of a bigger block of mass 10 M as shown in figure. All the surfaces are frictionless. The system is released from rest, then the distance moved by the bigger block at the instant the smaller block reaches the ground : A. 0.22 mB. 0.20 mC. zeroD. 0.24 m |
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Answer» Correct Answer - B |
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| 6. |
In an elastic collision of two billiard balls which of the following quantities is not conserved during the short time of collision :A. MomentumB. Total mechanical energyC. Kinetic energyD. None |
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Answer» Correct Answer - C |
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| 7. |
When a block is placed on a wedge as shown in figure, the block starts sliding down and the wedge also start sliding on ground. All surfaces are rough. The centre of mass of `(` wedge `+` block `)` system will move. A. upwardsB. downwardsC. leftwardsD. rightwards |
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Answer» Correct Answer - B |
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| 8. |
As shown in the figure a body of mass `m` moving horizontally with speed `sqrt(3) m//s` hits a fixed smooth wedge and goes up with a velocity `1v_(t)` in the vertical direction. If `/_` of wedge is `30^(@)`, the velocity `v_(f)` will be `:` A. `3 m//s`B. `sqrt(3) m//s`C. `(1)/(sqrt(3))m//s`D. this is not possible |
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Answer» Correct Answer - B |
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| 9. |
Two balls with masses in the ratio of 1:2 moving in opposite direction have a head-on elastic collision. If their velocities before impact were in the ration of 3:1, then velocities after impact will have the ratio :A. `5 :3`B. `7:5`C. `4:5`D. `2:3` |
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Answer» Correct Answer - B |
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| 10. |
The system of the wedge and the block connected by a massless spring as shown in the figure is released with the spring in its natural length. Friction is absent. Maximum elongation in the spring will be A. `(3Mg)/(5k)`B. `(6Mg)/(5k)`C. `(4Mg)/(5k)`D. `(8Mg)/(5k)` |
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Answer» Correct Answer - B |
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| 11. |
Two massless string of length 5 m hang from the ceiling very near to each other as shown in the figure. Two balls `A` and `B` of masses `0.25kg` and `0.5kg` are attached to the string. The ball `A` is released from rest at a height `0.45m` as shown in the figure. The collision between two balls is completely elastic. Immediately after the collision, the kinetic energy of ball `B` is `1 J` The velocity of ball `A` just after the collision is A. `5 ms^(-1)` to the rightB. `5 ms ^(-1)` to the leftC. `1 ms^(-1)` to the rightD. `1 ms^(-1)` to the left |
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Answer» Correct Answer - D |
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| 12. |
A sphere strikes a wall and rebounds with coefficient of restitution `(1)/(3)`. If it rebounds with a velocity of `0.1 m//sec` at an angle of `60^(@)` to the normal to the wall, the loss of kinetic energy is :A. `50%`B. `33(1)/(3)%`C. `40%`D. `66(2)/(3)%` |
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Answer» Correct Answer - D |
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| 13. |
A parallel beam of particles of mass `m` moving with velocity `v` impinges on a wall at an angle `theta` to its normal. The number of particles per unit volume in the beam is `n`. If the collision of particles with the wall is elastic, then the pressure exerted by this beam on the wall is |
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Answer» Correct Answer - B |
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| 14. |
In the diagram shown, no friction at any contact surface. Initially, the spring has no deformation what will be the maximum deformation in the spring? Consider all the strings to be sufficiency large. Consider the spring constant to be K. |
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Answer» Correct Answer - B |
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| 15. |
A man weighing 80 kg is standing at the centre of a flat boat and he is 20 m from the shore. He walks 8 m on the boat towards the shore and then halts.The boat weight 200 kg. How far is he from the shore at the end of this time ?A. 11.2 mB. 13.8 mC. 14.3 mD. 15.4 m |
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Answer» Correct Answer - C |
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| 16. |
A set of n identical cubical blocks lies at rest parallel to each other along a line on a smooth horizontal surface. The separation between the near surfaces of any two adjacent blocks is L . The block at one end is given a speed v towards the next one at time 0 t . All collisions are completely inelastic, thenA. The last block starts moving at `t=((n+1)L)/(v)`B. The last block starts moving at `t=(n(n-1)L)/(2v)`C. The center of mass of the system will have the final speed vD. The center of mass of the system will have the final speed `(v)/(n)` |
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Answer» Correct Answer - D |
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| 17. |
If collision takes place between 2 particles then which of the following statement is/are true :A. kinetic energy is conserved during collisionB. momentum is conserved during collisionC. momenutm is conserved only before and after collisonD. conservation of momentum during collision depends on the type of collision |
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Answer» Correct Answer - B |
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| 18. |
All the particles of a body situated at distance `d` from the origin. The distance of the center of mass of the body from the origin isA. `=R `B. `le R`C. `gt R`D. `ge R` |
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Answer» Correct Answer - B |
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| 19. |
A disc of radis R is cut out from a larger disc of radius 2R in such a way that the edge of the hole touches the edge of the disc. Locate the centre of mass of the residual disc.A. at `(2R)/(3)` from center of the original disc away from the center of the holeB. at `( R)/(3)` from center of the original disc away from the center of the holeC. at the center of the original discD. at the center of the hole |
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Answer» Correct Answer - B |
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| 20. |
A body falling vertically downwards under gravity breaks in two parts of unequal masses. The centre of mass of the two parts taken together shifts horizontally towardsA. heavier pieceB. lighter pieceC. does not shift horizontallyD. depends on the vertical at the time of breaking |
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Answer» Correct Answer - C |
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| 21. |
Two trains A and B are running in the same direction on the parallel rails such that A is faster than B. Packets of equal weight are transfcrred from A to B. What will happen due to this :A. A will be accelerated and B will be retardedB. B will be accelerated and A will be retardedC. There will be no change in A but B will be acceleratedD. There will be no change in B but A will be accelerated |
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Answer» Correct Answer - B |
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| 22. |
In the shown figure both blocks are in equilibrium m=1 kg. a bullet of mass m moves with velocity `10 m//s` and get embedded into the block A, then just after collision : A. `upsilon _(A)=(upsilon_(0))/(2),upsilon_(B)=0`B. `upsilon_(A)=upsilon_(B)=(upsilon_(0))/(2)`C. `upsilon_(A)=upsilon_(B)`=zeroD. `upsilon_(A)=upsilon_(B)=(upsilon_(0))/(3)` |
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Answer» Correct Answer - A |
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| 23. |
A spaceship travelling along `+y` axis with speed `v_(0)` suddenly shoots out one fourth of its parts with speed `2v_(0)` along `+x`-axis. `xy` axes are fixed with respect to ground. The velocity of the remaining part isA. `(2)/(3) upsilon_(0)`B. `(sqrt(20))/(3)upsilon_(0)`C. `(sqrt(5))/(3)upsilon_(0)`D. `(sqrt(13))/(3) upsilon_(0)` |
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Answer» Correct Answer - B |
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| 24. |
An open water tight railway wagon of mass `5 xx 10^(3) kg` moves at an initial velocity `1.2 m//s` without friction on a railway track. Rain drops fall vertically downwards into the wagon. The velocity of the wagon after it has collected`10^(3) kg` of water will be :-A. `0.5 m//s`B. `2 m//s`C. `1 m//s`D. `1.5 m//s` |
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Answer» Correct Answer - A |
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| 25. |
An open water tight railway wagon of mass `5xx10^(3)` kg coasts at initial velocity of `1.2 m//s` without friction on a railway track. Rain falls vertically downwards into the wagon. What change then occurred in the kinetic energy of the wagon, when it has collected `10^(3)` kg of waterA. 1200 JB. 300 JC. 600 JD. 900 J |
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Answer» Correct Answer - C |
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| 26. |
Three identical balls are connected by light inextensible strings with each other as shown and rest over a smooth horizontal table. Length of each string is `l`. At moment `t = 0`, ball `B` is imparted a velocity `v_(0)` perpendicular to the strings and then the system is left on its own. Calculate the velocity of `B` just before `A` collides with ball `C`.A. `9 m//s`B. zeroC. `3 m//s`D. `6 m//sec` |
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Answer» Correct Answer - C |
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| 27. |
Select the graph (s) which best represent the graph of bouncing ball. Assume ball dropped from height and it losses certain part of energy in each impact, A. 1,2,3,4B. 1,2,4C. 3,2D. 3,4 |
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Answer» Correct Answer - B |
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| 28. |
A is a fixed point at height H above a perfectly inelastic smooth horizontal plane. A light inextesnsible string of length `L(gtH)` has one end attached to A and other to a heavy particle. The particle is held at the level of A with string just taut and released from rest. Find the height of the particle above the plane when it is next instaneously at rest . A. velocity of particle on the surface is `=sqrt(2gh) cos theta`B. velocity of particle when it leaves surface `=sqrt(2gh) cos^(2) theta`C. `S=(h^(5))/(l^(4))`D. None of these |
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Answer» Correct Answer - D |
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| 29. |
A uniform sphere is placed on a smooth horizontal surface and a horizontal force F is applied on it at a distance h above the surface. The acceleration of the centre :A. is maximum when h=0B. is maximum when h=RC. is maximum when h=2RD. is independent of h |
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Answer» Correct Answer - D |
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| 30. |
Consider the following two statements: A The linear momentum of a particle is independent of the frame of reference. B. The kinetic energy of a particle is independent of the frame of referenceA. Both (i) and (ii) are trueB. (i) is true but (ii) is falseC. (i) is false but (ii) is trueD. both (i) and (ii) are false |
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Answer» Correct Answer - D |
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| 31. |
When the momentum of a body increases by 100%, its K.E. increases by :A. 4B. 1C. 3D. none |
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Answer» Correct Answer - C |
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| 32. |
Which of the following graphs represents the graphical relation between momentum (p) and kinetic energy (K) for a body in motion?A. B. C. D. None |
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Answer» Correct Answer - D |
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| 33. |
A ball strikes a smooth horizontal ground at an angle of `45^(@)` with the vertical. What cannot be the possible angle of its velocity with the vertical after the collisioin. (Assume `ele1`).A. `45^(@)`B. `30^(@)`C. `53^(@)`D. `60^(@)` |
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Answer» Correct Answer - B |
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| 34. |
A hemisphere of mass 3m and radius R is free to slide with its base on a smooth horizontal table. A particle of mass m is placed on the top of the hemisphere. If particle is displaced with a negligible velocity, then find the anuglar velocity of the particle relative to the centre of the hemisphere at an angular displacement `theta`, when velocity of hemisphere is `upsilon`. A. `(4 upsilon)/(R cos theta)`B. `(3 upsilon)/(R cos theta)`C. `(5 upsilon)/(R cos theta)`D. `(2 upsilon)/(R cos theta)` |
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Answer» Correct Answer - A |
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| 35. |
Two identical balls `A` and `B` are released from the position shown in Fig. They collide elastically with each other on the horizontal portion. The ratio of heights attained by `A` and `B` after collision is (neglect friction) A. `1:4`B. `2:1`C. `4:13`D. `2:5` |
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Answer» Correct Answer - C |
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| 36. |
Two ball `A` and `B` having masses 1kg and 2kg, moving with speeds `21m//s` amd `4m//s` receptively in opposite direction, collide head on. After collision `A` moves with a speed of `1m//s` in the same direction, then correct statements is:A. `0.1`B. `0.2`C. `0.4`D. none |
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Answer» Correct Answer - B |
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