6.6 Underline the correct alternative:

(a) When a conservative force does positive work on a body, the potential energy of the body increases/decreases/remains unaltered.

(b) Work done by a body against friction always results in a loss of its kinetic/potential energy.

(c) The rate of change of total momentum of a many-particle system is proportional to the external force/sum of the internal forces on the system.

(d) In an inelastic collision of two bodies, the quantities which do not change after the collision are the total kinetic energy/total linear momentum/total energy of the system of two bodies.

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9 months ago

6.6 (a) When a conservative force does positive work on a body, the body gets displaced in the direction of the force, it moves towards the centre of the force, thus resulting in decrease of potential energy.

(b) When the work done by a body against friction, it reduces its velocity. Hence kinetic

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