When the direction of the force and displacement are opposite, work done is:
Correct answer: A. Negative
- A. Negative
- B. Positive
- C. Zero
- D. None of these
Explanation
According to the formula, W = FdcosθIf both force and displacement are opposite in direction, then θ = 180o W = Fd cos180oWe know cos 180o = -1 W = Fd (-1) W = -FdHence, the work done will be negative. So, option A is the correct option.
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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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