Question
A coolie carrying a load on his head and moving on a frictionless horizontal platform does no work. Explain the reason why.
✓
Answer
We know W = F d cos θ.
Since force is normal to displacement.
So θ = 90°
Hence work done W = Fd cos θ 90 = 0.
Since force is normal to displacement.
So θ = 90°
Hence work done W = Fd cos θ 90 = 0.
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