Q 11-05-023NEETEAMCET 2012 (Medical)Easy
The displacement of a body is $(5\hat{i} + 3\hat{j} - 4\hat{k})$ m due to the action of a force $(6\hat{i} + 6\hat{j} + 4\hat{k})$ N on it for $5$ s. The power in watt is
Answer: (C) $6.4$
$$W = \vec{F}\cdot\vec{s} = 30 + 18 - 16 = 32\ \text{J}, \qquad P = \frac{W}{t} = \frac{32}{5} = 6.4\ \text{W}$$
Solution by Sreeraj P, M.Sc Physics