When brakes are applied to moving vehicle, the work done by the braking system is?
Correct answer: B. Negative
- A. Positive
- B. Negative
- C. Zero
- D. None of these
Explanation
Option A : The car is moving and suddenly when brakes are applied, the car stops and before stopping it comes a little backwards with a sudden push. But the forces are in opposite directions. So, work done will never be positive. it will be negative. Option: B When the work done on the body and the force acting on the body are opposite, the work done will be negative. In the given case, the work done is against the moving vehicle. so, the work done will be negative. Option C : As both forces are in opposite directions, so work done will never be zero.
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About Work
Work is done when a force produces displacement, with its value determined by the component of force along the displacement. The topic covers positive, negative and zero work, work by variable forces from force-displacement graphs, and the connection between net work and change in kinetic energy.
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