Work, Energy and Power · Physics · NEET

A particle moves with a velocity $$(5 \hat{i}-3 \hat{j}+6 \hat{k}) ~\mathrm{ms}^{-1}$$ horizontally under the action of constant force $$(10 \hat{\mat...

The potential energy of a long spring when stretched by $$2 \mathrm{~cm}$$ is U. If the spring is stretched by $$8 \mathrm{~cm}$$, potential energy st...

The restoring force of a spring with a block attached to the free end of the spring is represented by

An electric lift with a maximum load of 2000 kg (lift + passengers) is moving up with a constant speed of 1.5 ms$$-$$1. The frictional force opposing ...

The energy that will be ideally radiated by a 100 kW transmitter in 1 hour is

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 he...

Water falls from a height of 60m 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...

A force F = 20 + 10y acts on 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...

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 ...

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$$-$$1. Take 'g' constant with a...

A particle moves from a point $$\left( { - 2\widehat i + 5\widehat j} \right)$$ to $$\left( {4\widehat j + 3\widehat k} \right)$$ when a force of $$\l...

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 t...

A body of mass 1 kg begins to move under the action of a time dependent force $$\overrightarrow F = \left( {2t\widehat i + 3{t^2}\widehat J} \right)N...

What is the minimum velocity with which a body of mass m must enter a vertical loop of radius R so that it can complete the loop?

Two particles A and B, move with constant velocities $$\overrightarrow {{v_1}} $$ and $$\overrightarrow {{v_2}} $$. At the initial moment their positi...

A ball is thrown vertically downwards from a height of 20 m with an initial velocity v0. It collides with the ground, losses 50 percent of its energy ...

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 $$ \...

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. Afte...

A block of mass 10 kg, moving in x direction with a constant speed of 10 m s$$-$$1, is subjected to a retarding force F = 0.1x J/m during its travel f...

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...

Two similar springs P and Q have spring constants KP and KQ, such that KP > KQ. They are stretched first by the same amount (case a), then by the s...

A particle with total energy E is moving in a potential energy region U(x). Motion of the particle is restricted to the region when

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. ...

A uniform force of $$\left( {3\widehat i + \widehat j} \right)$$ newton acts on a particle of mass 2 kg. Hence the particle is displaced from position...

A car of mass m starts from rest and accelerates so that the instantaneous power delivered to the car has a constant magnitude P0. The instantaneous v...

The potential energy of a particle in a force field is $$U = {A \over {{r^2}}} - {B \over r}$$ where A and B are positive constants and r is the dista...

A solid cylinder of mass 3 kg is rolling on a horizontal surface with velocity 4 m s$$-$$1. It collides with a horizontal spring of force constant 200...

A mass m moving horizontally (along the x-axis) with velocity $$v$$ collides and sticks to a mass of 3m moving vertically upwards (along the y-axis) w...

The potential energy of a system increases if work is done

Force F on a particle moving in a straight line varies with distance d as shown in figure. The work done on the particle during its displacement of ...

A body projected vertically from the earth reaches a height equal to earth's radius before returning to the earth. The power exerted by the gravitatio...

A particle of mass m is released from rest and follows a parabolic path as shown. Assuming that the displacement of the mass from the origin is small,...

A particle of mass M, starting from rest, undergoes uniform acceleration. If the speed acquired in time T is V, the power delivered to the particle is...

A ball moving with velocity 2 m/s collides head on with another stationary ball of double the mass. If the coefficient of restitution is 0.5, then the...

An engine pumps water through a hose pipe. Water passes through the pipe and leaves it with a velocity of 2 m/s. The mass per unit length of water in ...

A body of mass 1 kg is thrown upwards with a velocity 20 m/s. It momentarily comes to rest after attaining a height of 18 m. How much energy is lost d...

A block of mass M is attached to the lower end of a vertical spring. The spring is hung from a ceiling and has force constant value k. The mass is rel...

An engine pumps water continuously through a hose. Water leaves the hose with a velocity v and m is the mass per unit length of the water jet. What is...

Water falls from a height of 60 m at the rate of 15 kg/s to operate a turbine. The losses due to frictional forces are 10% of energy. How much power i...

A vertical spring with force constant k is fixed on a table. A ball of mass m at a height h above the free upper end of the spring falls vertically on...

300 J of work is done in sliding a 2 kg block up an inclined plane of height 10 m. Work done against friction is (Take g = 10 m/s2)

A body of mass 3 kg is under a constant force which causes a displacement s in metres in it, given by the relation s = $${1 \over 3}$$t2, where t is i...

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

A force F acting on an object varies with distance x as shown here. The force is in N and x in m. The work done by the force in moving the object fr...

A ball of mass 2 kg and another of mass 4 kg are dropped together from a 60 feet ball building. After a fall of 30 feet each towards earth, their resp...

A particle of mass m1 is moving with a velocity v1 and another particle of mass m2 is moving with a velocity v2. Both of them have the same momentum...

A mass of 0.5 kg moving with a speed of 1.5 m/s on horizontal smooth surface, collides with a nearly weightless spring of force constant k = 50 N/m. T...

A particle moves along a circle of radius $$\left( {{{20} \over \pi }} \right)$$ m with constants tangential acceleration. If the velocity of vthe pa...

When a long spring is stretched by 2 cm, its potential energy is U. If the spring is stretched by 10 cm, the potential energy stored in it will be

A child is sitting on a swing. Its minimum and maximum heights from the ground 0.75 m and 2 m respectively, its maximum speed will be

A particle is projected making an angle of 45o with horizontal having kinetic energy K. The kinetic energy at highest point will be

Two springs A and B having spring constant KA and KB (KA = 2KB) are stretched by applying force of equal magnitude. If energy stored in spring A is EA...

If $$\overrightarrow F = \left( {60\widehat i + 15\widehat j - 3\widehat k} \right)$$ N and $$\overrightarrow v = \left( {2\widehat i - 4\widehat j ...

A mass of 1 kg is thrown up with a velocity of 100 m/s. After 5 seconds, it explodes into two parts. One part of mass 400 g comes down with a velocity...