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A force of 7 N acts on an object. The displacement is, say 8 m, in the direction of the force (see the given figure). Let us take it that the force acts on the object through the displacement.

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Question

A force of 7 N acts on an object. The displacement is, say 8 m, in the direction of the force (see the given figure). Let us take it that the force acts on the object through the displacement. What is the work done in this case?

Numerical
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Solution

When a force F acts on an object to displace it through a distance S in its direction, then the work done to the body by the force is given by:

Work done = Force × Displacement

W = F × S

Where,

F = 7 N

S = 8 m

Therefore, work done, W = 7 × 8

= 56 Nm

= 56 J

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Chapter 10: Work and Energy - Intext Questions [Page 115]

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NCERT Science [English] Class 9
Chapter 10 Work and Energy
Intext Questions | Q 1. | Page 115

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