Work Done by a Variable Force

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Work Done by a Variable Force: Overview

This topic consists of various concepts like Work Done by Variable Force,Work as Area under Force-Displacement Graph,, etc.

Important Questions on Work Done by a Variable Force

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A force F=2+3xi^ acts on a particle in the x direction where F is in Newton and x is in meter. The work done by this force during a displacement from x = 0 to x=4 m is _____ J.

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A block of mass 10 kg is moving along x-axis under the action of force F=5x N. The work done by the force in moving the block from x=2 m to 4 m will be _______ J.

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A variable force F=5Kx N acts on a body moving along x-axis. Find the work done by this force in displacing the body from x= 2 m to x=5 m (K is a constant).

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Force acting on a particle moving along x-axis is given by F=(2+3x)i^. The work done by this force from x=0 to x=4 m is

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A particle starts to move along the path which locus is given as x2=(8y) (x&y are in m), due to applied force F=(axi^+byj^ ) N (a>0 and b>0 and x & y are in metre). The amount of work done in displacing particle from x=0 to x=1 metre is

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A force, F=(10+x) N acts on a particle of mass 4 kg in x direction, where x is in meter. Find the work done by the force during the time interval its acceleration changes from 2.5 m s-2 to  5.0 m s-2
 

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A particle of mass 0.5 kg is subjected to a force which varies with distance as shown in graph

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If the speed of the particle at x= 0 is 4 m s-1, then its speed at x=8 m is

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If the potential energy at point O (0, 0) is U0= 10 J, find the potential energy at point D (4, 0) corresponding to the given graph.

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Calculate the net work done by the force F whose variation with position has been shown as above.

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The area of the acceleration-displacement curve of a body gives

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A block of mass is placed at origin (0, 0) and a force, F=(2x + 2) N, is applied on the block that it reaches at some other point. P (5, 0). Find the work done by the force.
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A block of mass m is placed at origin 0,0 and a force, F=2+2x N, is applied on the block so that it reaches at some other point, P 5,0. Find the work done by the force.

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Calculate the net work done by the force F whose variation with position has been shown as above.

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A force F=kyi^+xj^ N where k is a positive constant act on a particle moving in x-y plane starting from the point 3,5, the particle is taken along a straight line to 5,7. The work done by the force is:

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A particle is moving in anticlockwise direction in a circle under the influence of a force,  F= x2-yi^+x+5y-zj^+3x-4y+zk^ N, where x, y and z are in meter. The circle lies on the xy-plane with its center at the origin and has a radius of 2 m. The work done by the force as the particle completes one revolution is (in Joule)[Take π= 3.14]

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Force acting on a particle varies with displacement as shown in figure. The workdone by this force on the particle from x=-8 m to x=+8 m

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A small block of mass m is moving under the effect of a force which is given by F=3xj^+3yi^N. If this force displaces the block from point A2 m,3 m to another point B1 m,4 m, then work done by the force will be

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While calculating work done by a variable force, why do we calculate the work done for small displacements x?

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If the force on a body is varying, then how will you find the work done by the force?

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A position-dependent force F=7-2x+3x2 newton acts on a small body of mass 2 kg and displaces it from x=0 to x=5. Calculate the work done.