Question 1 :
A body is acted upon by a force $ F = \hat{i} + 2 \hat{j} + 3 \hat{k} $ . The work done by the force in displacing it from $ (0, 0, 0) $ to $ (0,0,4m)$ will be -
Question 2 :
A particle is taken round a circle by application of force. The work done by the force is
Question 3 :
A body is moved along a straight line by a machine delivering constant power. The distance moved by the body in time t is proportional to
Question 4 :
Two bodies {tex} A {/tex} and {tex} B {/tex} having masses in the ratio of 3: 1 possess the same kinetic energy. The ratio of linear momentum of {tex} B {/tex} to {tex} A {/tex} is
Question 5 :
A boy pushes a toy box {tex} 2.0 \mathrm { m } {/tex} along the floor by means of a force of {tex} 10 \mathrm { N } {/tex} directed downward at an angle of {tex} 60 ^ { \circ } {/tex} to the horizontal. The work done by the boy is
Question 6 :
Two blocks of masses {tex} m _ { 1 } = 10 \mathrm { kg } {/tex} and {tex} m _ { 2 } = 20 \mathrm { kg } {/tex} are connected by a spring of stiffness {tex} k = 200 \mathrm { N } / \mathrm { s } {/tex} {tex} \mathrm { m } {/tex}. The coefficient of friction between the blocks and the fixed horizontal surface is {tex} \mu = 0.1 . {/tex} Find the minimum constant horizontal force {tex} F {/tex} (in newtons) to be applied to {tex} \mathrm { m } _ { 1 } {/tex} in order to slide the mass {tex} m _ { 2 } . {/tex} <br> [Take {tex} \mathrm {g= 10 m/s ^2}{/tex}
Question 7 :
When the force retards the motion of body, the work done is
Question 8 :
One man takes {tex} 1 \mathrm { min } {/tex}. to raise a box to a height of {tex}1{/tex} metre and another man takes {tex} 1 / 2 \mathrm { min } {/tex}. to do so. The energy of the
Question 9 :
A particle moves in a straight line with retardation proportional to its displacement. Its loss of kinetic energy for any displacement {tex} x {/tex} is proportional to
Question 10 :
The work done on a particle of mass $m$ by a force $K \left[\dfrac{x}{(x<br>^{2}+y^{2})^{3/2}}\hat{i}+\dfrac{y}{(x^{2}+y^{2})^{3/2}}\hat{j} \right] $, where $K$ being a constant of appropriate dimensions, when the particle is taken from the point $(a,\ 0)$to the point $(0,\ a)$along a circular path of radius $a$ about the origin in the x-y plane is:<br>
Question 11 :
A mass of {tex} 20 \mathrm { kg } {/tex} moving with a speed of {tex} 10 \mathrm { m } / \mathrm { s } {/tex} collides with another stationary mass of {tex} 5 \mathrm { kg } {/tex}. As a result of the collision, the two masses stick together. The kinetic energy of the composite mass will be
Question 12 :
A force {tex} F = - K ( y \hat { i } + x \hat { j } ) {/tex} (where {tex} K {/tex} is a positive constant) acts on a particle moving in the {tex} x y {/tex} plane. Starting from the origin, the particle is taken along the positive {tex} x {/tex} axis to the point {tex} ( a , 0 ) , {/tex} and then parallel to the {tex} y {/tex} axis to the point {tex} ( a , a ) , {/tex} The total work done by the force {tex} F {/tex} on the particle is
Question 13 :
A car of mass {tex} m {/tex} starts from rest and accelerates so that the instantaneous power delivered to the car has a constant magnitude {tex} p _ { 0 } {/tex}. The instantaneous velocity of this car is proportiourl to:
Question 14 :
How much water, a pump of {tex} 2 \mathrm { kW } {/tex} can raise in one minute to a height of {tex} 10 \mathrm { m } , {/tex} take {tex} \mathrm { g } = 10 \mathrm { m } / \mathrm { s } ^ { 2 } ? {/tex}
Question 15 :
A vehicle of mass $M$ is accelerated on a horizontal frictionless road under a force changing its velocity from $u$ to $v$ and distance covered is $S$. A constant power $P $ is given by the engine of the vehicle. The $v$ is equal to
Question 16 :
A body of mass 1 kg begins to move under the action of a time dependent force {tex} \vec F{/tex} = (2t{tex} \hat i{/tex}+3{tex}t^2 \hat j{/tex})N, where {tex} \hat i{/tex}and {tex} \hat j{/tex} are unit vectors along x and y axis. What power will be developed by the force at the time t?
Question 17 :
A <b>10 m</b> long iron chain of linear mass density <b>0.8 kgm<sup>-1</sup></b> is hanging freely from a rigid support. If <b>g = 10 ms<sup>-2</sup></b>, then the power required to left the chain upto the point of support in 10 second
Question 18 :
An object of mass <b>2kg </b> makes an elastic collision with another object of mass <b> M </b> at rest and continues to move in the original direction but with one-fourth of its original speed. What is the value of <b>M </b>?
Question 19 :
A particle moves under the effect of a force {tex} \mathrm { F } = \mathrm { cx } {/tex} from {tex} \mathrm { x } = 0 {/tex} to {tex} \mathrm { x } = \mathrm { x } _ { 1 } , {/tex} the work done in the process is
Question 20 :
The coefficient of restitution e for a perfectly elastic collision is
Question 21 :
A boy carrying a box on his head is walking on a level road from one place to another is doing no work. This statement
Question 22 : A block of mass {tex} 1 \mathrm { kg } {/tex} is pulled along the curve path {tex} \mathrm {A C B }{/tex} by a tangential force as shown in figure. The work done by the frictional force when the block moves from {tex} \mathrm A {/tex} to {tex}\mathrm B {/tex} is<br><img style='object-fit:contain' src="https://storage.googleapis.com/teachmint/question_assets/NEET/5e0ee6688420d95285473c80"><br>
Question 23 :
A bullet is fired and gets embedded in block kept on table. If table is frictionless, then
Question 24 :
If a shell fired from a cannon, explodes in mid air, then
Question 25 : If W represents the work done, then match the two columns:<br><table>
<tr><th>Column I </th> <th>Column II</th> </tr>
<tr><td>(A)Force is always along the velocity</td> <td>(1)W=0</td> </tr>
<tr><td>(B)Force is always perpendicular to velocity </td> <td>(2)W<0</td> </tr>
<tr><td>(C)Force is always perpendicular to acceleration</td> <td>(3)W>0</td> </tr>
<tr><td>(D)The object is stationary but the point of application of the force moves on the object</td> <td></td> </tr>
</table>
Question 26 :
A body of mass {tex} 0.5 \mathrm { kg } {/tex} travels in a straight line with velocity {tex} v = 5 x ^ { 3 / 2 } . {/tex} The work done by the net force during the displacement from {tex} x = 0 {/tex} to {tex} x = 2 \mathrm { m } {/tex} is
Question 27 :
An athlete in the olympic games covers a distance of {tex} 100 \mathrm { m } {/tex} in {tex} 10 \mathrm { s } {/tex}. His kinetic energy can be estimated to be in the range
Question 28 :
A vehicle is moving with a uniform velocity on a smooth horizontal road, then power delivered by its engine must be
Question 29 :
A uniform chain of length 2 m is kept on a table such that a length of 60 cm hangs freely from the edge of the table. The total mass of the chain is 4 kg. What is the work done in pulling the entire chain on the table?
Question 30 :
A body moves a distance of {tex} 10 \mathrm { m } {/tex} along a straight line under the action of a force of {tex}5{/tex} newtons. If the work done is {tex}25{/tex} joules, the angle which the force makes with the direction of motion of body is
Question 31 :
The work done in sliding a wooden box of mass $5\ kg$ along a friction less inclined plane of inclination ${30}^{o}$ and length $10\ m$ is______$J$. $(g=10\ {ms}^{-2})$
Question 32 :
A bullet of mass {tex} 20 \mathrm { g } {/tex} and moving with {tex} 600 \mathrm { m } / \mathrm { s } {/tex} collides with a block of mass {tex} 4 \mathrm { kg } {/tex} hanging with the string. What is velocity of bullet when it comes out of block, if block rises to height {tex} 0.2 \mathrm { m } {/tex} after collision?
Question 33 :
A man of weight $50\  kg$ carries an object to a height of $20\ m$ in a time of $10\  s$. The power used by the man in the this process is $2000\ W$, then find the mass of the object carried by the man.<br/>[assume $g= 10 ms^{-2}]$
Question 34 :
The power required to keep the belt moving is ____ $\dfrac{d}{dt}$ (KE)
Question 35 :
A spherical ball of mass {tex} 20 \mathrm { kg } {/tex} is stationary at the top of a hill of height {tex} 100 \mathrm { m } {/tex}. It rolls down a smooth surface to the ground, then climbs up another hill of height {tex} 30 \mathrm { m } {/tex} and finally rolls down to a horizontal base at a height of {tex} 20 \mathrm { m } {/tex} above the ground. The velocity attained by the ball is
Question 36 :
The kinetic energy of particle moving along a circle of radius R depends upon the distance covered S and is given by {tex}K = aS^2{/tex} where a is a constant. Then the force acting on the particle is
Question 37 :
In an inelastic collision, which of the following does not remain conserved?
Question 38 :
A uniform force of {tex} ( 3 \hat { i } + \hat { j } ) {/tex} newton acts on a particle of mass {tex} 2 \mathrm { kg } {/tex}. The particle is displaced from position {tex} ( 2 \hat { i } + \hat { k } ) {/tex} meter to position {tex} ( 4 \hat { i } + 3 \hat { j } - \hat { k } ) {/tex} meter. The work done by the force on the particle is
Question 39 :
In elastic collision, {tex} 100 \% {/tex} energy transfer takes place when
Question 40 :
A body of mass {tex} 1 \mathrm { kg } {/tex} begins to move under the action of a time dependent force {tex} \vec { \mathrm { F } } = \left( 2 \mathrm { t } \hat { \mathrm { i } } + 3 \mathrm { t } ^ { 2 } \hat { \mathrm { j } } \right) \mathrm { N } {/tex} where {tex} \hat { \mathrm { i } } {/tex} and {tex} \hat { \mathrm { j } } {/tex} are unit vectors along {tex} \mathrm { x } {/tex} and {tex} \mathrm { y } {/tex} axis. What power will be developed by the force at the time {tex} \mathrm {t} {/tex} ?
Question 41 :
When after collision the deformation is not relived and the two bodies move together after the collision, it is called
Question 42 :
Johnny and his sister Jane race up a hill. Johnny weighs twice as much as jane and takes twice as long as jane to reach the top. Compared to Jane
Question 43 :
One end of a light spring of spring constant {tex} k {/tex} is fixed to a wall and the other end is tied to a block placed on a smooth horizontal surface. In a displacement, the work done by the spring is {tex} 1 / 2 \mathrm { k } \mathrm { x } ^ { 2 } {/tex}. The possible cases are
Question 44 : A uniform rope of linear mass density {tex} \lambda {/tex} and length {tex} \ell {/tex} is coiled on a smooth horizontal surface. One end is pulled up with constant velocity {tex} v {/tex}. Then the average power applied by the external agent in pulling the entire rope just off the horizontal surface is<br><img style='object-fit:contain' src="https://storage.googleapis.com/teachmint/question_assets/NEET/5e0ee88fdc973f528b538dec"><br>
Question 45 :
A {tex} 2 \mathrm { kg } {/tex} block slides on a horizontal floor with a speed of {tex} 4 \mathrm { m } / \mathrm { s } {/tex}. It strikes a uncompressed spring, and compresses it till the block is motionless. The kinetic friction force is {tex} 15 \mathrm { N } {/tex} and spring constant is {tex} 10,000 \mathrm { N } / \mathrm { m } {/tex}. The spring compresses by
