A body is moving unidirectionally under the influence of a source of constant power. Its displacement in time t is proportional to

(i) t1/2 (ii) t (iii) t3/2 (iv) t2

The correct answer is (iii).

Explanation:


Power, P = F v = k (constant)


Considering the dimensions,


[P] = [F][v]


[P] = [MLT-2][LT-1]


[P] = [ML2T-3]


So, [ML2T-3] = k


[L2T-3] = k


[L2/T3] = k


[L2] = k[T3]


[L2] [T3]


[L] [T3/2]


Hence, l t3/2


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