Give reason for the following: Why a coolie does not work, when he mo

1.	Give reason for the following: Why a coolie does not work, when he moves on a level road while carrying a box on his head?
Answer» Work done when force is applied at an angle to motion is given by: W= F×S cos θ Where F = force S = displacement θ = angle between the direction of force and direction of motion. Work done by a coolie in carrying a load on his head is ZERO with respect to gravity. This is because the coolie applies force against the force of gravity which acts in a vertically downward direction and displacement of load takes place in a horizontal direction hence the angle between displacement and force becomes 90°. cos 90°= 0 which means work done = 0 So, a coolie does not work, when he moves on a level road while carrying a box on his head.

Give reason for the following: Why a coolie does not work, when he moves on a level road while carrying a box on his head?

Answer»

Work done when force is applied at an angle to motion is given by:

W= F×S cos θ

Where F = force

S = displacement

θ = angle between the direction of force and direction of motion.

Work done by a coolie in carrying a load on his head is ZERO with respect to gravity. This is because the coolie applies force against the force of gravity which acts in a vertically downward direction and displacement of load takes place in a horizontal direction hence the angle between displacement and force becomes 90°.

cos 90°= 0 which means work done = 0

So, a coolie does not work, when he moves on a level road while carrying a box on his head.

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