List of top Physics Questions on work, energy and power asked in NEET (UG)

An object moving along horizontal x-direction with kinetic energy \(10 \, \text{J}\) is displaced through \(\mathbf{x} = (3\mathbf{i}) \, \text{m}\) by the force \(\mathbf{F} = (-2\mathbf{i} + 3\mathbf{j}) \, \text{N}\). The kinetic energy of the object at the end of the displacement \(\mathbf{x}\) is:
An object falls from a height of 10 m above the ground. After striking the ground it loses $50\%$ of its kinetic energy. The height upto which the object can rebounce from the ground is:
Two heaters A and B have power rating of 1 kW and 2 kW, respectively. Those two are first connected in series and then in parallel to a fixed power source. The ratio of power outputs for these two cases is :
At any instant of time t, the displacement of any particle is given by 2t – 1 (SI unit) under the influence of force of 5N. The value of instantaneous power is (in SI unit):

The potential energy of a long spring when stretched by 2 cm is U. If the spring is stretched by 8 cm, potential energy stored in it will be:

Water falls from a height of 60 m at the rate of 15 kg/s to operate a turbine. The losses due to frictional force are 10% of the input energy. How much power is generated by the turbine (g=10 m/s2)
A particle is released from height S from the surface of the Earth. At a certain height, its kinetic energy is three times its potential energy. The height from the surface of the earth and the speed of the particle at that instant are respectively
Find the torque about the origin when a force of $3 \,\hat{j}\, N$ acts on a particle whose position vector is $2\, \hat {k}\, m$ .
A force F = 20 + 10y action a particle in y-direction where F is in newton and y in meter. Work done by this force to move the particle from y = 0 to y = 1 m is :
A mass $m$ is attached to a thin wire and whirled in a vertical circle. The wire is most likely to break when:
A particle of mass 5 m at rest suddenly breaks on its own into three fragments. Two fragments of mass m each move along mutually perpendicular direction with speed v each. the energy released during the process is :
Body A of mass 4m moving with speed u collides with another body B of mass 2m, at rest. The collision is head on and elastic in nature. After the collision the fraction of energy lost by the colliding body A is :
A body initially at rest and sliding along a frictionless track from a height $h$ (as shown in the figure) just completes a vertical circle of diameter $AB \,=\, D$. The height h is equal to
Consider a drop of rain water having mass $1\,g$ falling from a height of $1\,km$. It hits the ground with a speed of $50\,m/s$. Take 'g' constant with a value ${10 \, m/s^2}$. The work done by the (i) gravitational force and the (ii) resistive force of air is :-
Two blocks A and B of masses 3m and m respectively are connected by a massless and inextensible string. The whole system is suspended by a massless spring as shown in figure. The magnitudes of acceleration of A and B immediately after the string is cut, are respectively
wo blocks A and B of masses 3m and m respectively are connected by a massless
A particle moves from a point $(-2 \hat{i} + 5 \hat{j})$ to $( 4 \hat{j} + 3 \hat{k})$ when a force of $(4 \hat{i} + 3 \hat{j} ) N$ is applied. How much work has been done by the force ?
A body of mass 1 kg begins to move under the action of a time dependent force $\vec{F} = ( 2\hat{i} + 3t^2 \hat{j} )N$, where $\hat{i}$ and $\hat{j}$ are unit vectors along x and y axis. What power will be developed by the force at the time t ?
A particle of mass $10\,g$ moves along a circle of radius $6.4\,cm$ with a constant tangential acceleration. What is the magnitude of this acceleration if the kinetic energy of the particle becomes equal to $8 \times 10^{-4} \, J$ by the end of the second revolution after the beginning of the motion ?
On a frictionless surface, a block of mass $M$ moving at speed $v$ collides elastically with another block of same mass $M$ which is initially at rest. After collision the first block moves at an angle $\theta$ to its initial direction and has a speed $\frac{v}{3}$. The second block's speed after the collision is
Two particles of masses m$_1$, m$_2$ move with initial velocities u$_1$ and u$_2$. On collision, one of the particles get excited to higher level, after absorbing energy $\varepsilon$. If final velocities of particles be v$_1$ and v$_2$ then we must have
A particle of mass m is driven by a machine that delivers a constant power k watts. If the particle starts from rest the force on the particle at time t is
The heart of a man pumps $5$ litres of blood through the arteries per minute at a pressure of $150 \,mm$ of mercury. If the density of mercury be $13.6 \times 10^3$ $kg/m^3$ and $g$ = $10\, m/s^2$ then the power
A body of mass $(4m)$ is lying in $x-y$ plane at rest. It suddenly explodes into three pieces. Two pieces, each of mass $(m)$ move perpendicular to each other with equal speeds $(v)$. The total kinetic energy generated due to explosion is
One coolie takes 1 minute to raise a suitcase through a height of 2 m but the second coolie takes 30 s to raise the same suitcase to the same height. The powers of two coolies are in the ratio
A uniform force of $(3 \hat{i} + \hat{j})$ newton acts on a particle of mass 2kg. Hence the particle is displaced from position$ (2\hat{i} + \hat{k} )$ meter to position $(4\hat{i} + 3\hat{j} - \hat{k})$ meter. The work done by the force on the particle is :