Work, Energy and PowerNEET Physics · Class 11 · NCERT Chapter 5

A force of $10\text{N}$ is applied at an angle of $60°$ with the horizontal on a body which moves $5\text{m}$ horizontally. The work done by the force is:

A body moves under the action of a force $\vec{F}=3\hat{i}+4\hat{j}\text{N}$ through a displacement $\vec{d}=5\hat{i}+12\hat{j}\text{m}$. The work done is:

A particle moves under the influence of a centripetal force in a circular path. The work done by the force in one full revolution is:

A body of mass $4\text{kg}$ moves with velocity $5\text{m/s}$. Its kinetic energy is:

If the momentum of a particle doubles, its kinetic energy becomes:

Two bodies of masses $1\text{kg}$ and $4\text{kg}$ have equal kinetic energies. The ratio of their momenta is:

A body of mass $2\text{kg}$ initially at rest is acted on by a force which varies as $F=4x\text{N}$ where $x$ is in metres. The kinetic energy gained when the body moves from $x=0$ to $x=2\text{m}$ is:

A body of mass $1\text{kg}$ moving with speed $5\text{m/s}$ is brought to rest by a constant force in $10\text{m}$. The magnitude of the force is:

A bullet of mass $20\text{g}$ moving with $200\text{m/s}$ penetrates a target through a distance of $10\text{cm}$. The average resistive force is:

A spring of force constant $800\text{N/m}$ is stretched from $5\text{cm}$ to $10\text{cm}$. The work done in this stretching is:

A spring of force constant $k$ is stretched by $x$. To increase its extension to $2x$, the additional work done is:

A body falls from a height $h$ onto a fixed pile, embedding to a depth $d$. The average resistive force exerted by the pile on the body of mass $m$ is:

A ball is dropped from a height of $20\text{m}$. Take $g=10{\text{m/s}}^2$. Just before hitting the ground, its speed is:

A simple pendulum of length $1\text{m}$ is released from a horizontal position. Take $g=10{\text{m/s}}^2$. The speed of the bob at the lowest point is:

A motor lifts $300\text{kg}$ of water through $20\text{m}$ in $1\text{minute}$. Take $g=10{\text{m/s}}^2$. Its power is:

A car moves up an incline at constant speed of $10\text{m/s}$. The total resistive force is $200\text{N}$. The power output of the engine is:

A pump can raise $100\text{kg}$ of water per minute against a head of $9\text{m}$. Take $g=10{\text{m/s}}^2$. The minimum power required is:

A body of mass $m$ moving with velocity $u$ collides head-on elastically with a body of equal mass at rest. After collision, the velocity of the first body is:

A bullet of mass $m$ moving with velocity $v$ hits a stationary block of mass $M$ and gets embedded. The fraction of original kinetic energy lost is:

Two bodies of masses $1\text{kg}$ and $2\text{kg}$ moving with velocities $4\text{m/s}$ and $-1\text{m/s}$ respectively collide head-on elastically. Their velocities after collision are:

A small body of mass $m$ is whirled in a vertical circle of radius $r$. Take $g=10{\text{m/s}}^2$, $r=0.4\text{m}$. The minimum speed at the highest point is:

In a vertical circular motion of radius $r$, the ratio of speeds at the lowest and highest points (for minimum speed cases) is:

A body is moved through a distance $d$ along a horizontal surface. The work done by the normal reaction force is:

If the kinetic energy of a body is doubled, its momentum becomes:

A body slides down a frictionless inclined plane of height $h$ (any angle). Its speed at the bottom is:

Two springs of force constants $k_1$ and $k_2$ are stretched by the same force. The ratio of energy stored is:

In a perfectly inelastic collision between two equal masses where one is at rest, the fraction of kinetic energy lost is:

A block of mass $2\text{kg}$ slides down a rough incline of length $5\text{m}$ and angle $30°$. The coefficient of kinetic friction is $0.2$. Take $g=10{\text{m/s}}^2$. The speed at the bottom (starting from rest) is:

A car of mass $1000\text{kg}$ accelerates uniformly from rest to $20\text{m/s}$ in $10\text{s}$. The average power is:

A spring gun of force constant $250\text{N/m}$ is compressed by $10\text{cm}$ and then used to launch a $50\text{g}$ ball horizontally. The launch speed is:

A force $F$ acting on a body produces a displacement $s$ in its direction. If the kinetic energy of the body is increased by $50\%$, the work done by $F$ is: