Question
How much work does a pulling force of $40 \,N$ do on the $20\, kg$ box in pulling it $8 \,m $ across the floor at a constant speed. The pulling force is directed at $60^o $ above the horizontal.....$J$
✓
Answer
(a) $W = \vec F.\vec s = 40 \times 8 \times \cos 60^\circ = 160\,J$
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