InterviewSolution
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InterviewSolution
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A body is moved along a straight line by a machine delivering constant power . The distance moved by the body is time `t` is proptional toA. (a) `sqrtt`B. (b) `t^(3//4)`C. (c) `t^(3//2)`D. (d) `t^2` |
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Answer» Correct Answer - C Let us assume that the displacement of the body is directly proportional to `t^n`, i.e., `s=Kt^n`, `v=(ds)/(dt)=Knt^(n-1)` and `a=(dv)/(dt)=Kn(n-1)t^(n-2)` Force `F=ma=mKn(n-1)t^(n-2)` Power, `P=Fv=[mKn(n-1)t^(n-2)][Knt^(n-1)]` `=mKn^2(n-1)t^(2n-3)` As power is constant, i.e. independent of time, hence `2n-3=0` or `n=3/2` or `spropt^(3/2)` |
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