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Question Question 2(vi)
(a) Derive the relation between CGS and SI unit of power.
(b) A man is holding a suitcase in his hand at rest. What is the work done by him?
(a) SI unit of power = watt = 1 J/s
∴ 1 W = 1 J/s = 105 dyne x 102 cm/s [∵ J = N-m]
= 107 erg/s [∵ dyne x cm = erg]
(b) Work done by the man is zero as his displacement is zero.