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प्रश्न
Work is a scalar quantity because it is a measure of transfer of energy without indicating any direction
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उत्तर
When the displacement of the body is in the direction opposite to that of the applied force,the work done is negative.
W = Fd cos 0 = Fd cos 180° = -Fd
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संबंधित प्रश्न
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`["Hint" : "Efficiency" = "useful power"/"power input"]`
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