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Karnataka Board PUCPUC Science Class 11

A Box is Pushed Through 4.0 M Across a Floor Offering 100 N Resistance. How Much Work is Done by the Resisting Force?

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Question

A box is pushed through 4.0 m across a floor offering 100 N resistance. How much work is done by the resisting force?

 
Sum
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Solution

Resisting force acting on the box, \[F = 100 N\]

Displacement of the box, S = 4 m

Also,

\[\theta = 180^\circ\]

∴ Work done by the resisting force,

\[W = \to_F \cdot \to_S = 100 \times 4 \times \cos180^\circ= - 400 J\]
 
 
 
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Chapter 8: Work and Energy - Exercise [Page 132]

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HC Verma Concepts of Physics Volume 1 and 2 [English]
Chapter 8 Work and Energy
Exercise | Q 3 | Page 132

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