A body is initially at rest. It undergoes one-dimensional motion with constant acceleration. The power delivered to it at time t is proportional to

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


The correct answer is (ii).

Explanation:


From Newton’s first equation of motion,


v = u + at


where, v is the final velocity


u is the initial velocity


a is the acceleration of the body


t is the time taken


Given, u = 0.


So, v = at


Power is given by


P = F × v


P = ma × at


P = ma2t


Since m and a are constant,


P t


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