A particle moves with velocity under the influence of a constant force

PHYSICS · Single correct · A Level · Physics · Mechanics and materials · Mechanics and materials

Problem

A particle moves with velocity

\mathbf{v} = (5\hat{\mathbf{i}} - 3\hat{\mathbf{j}} + 6\hat{\mathbf{k}})\,\text{m s}^{-1}

under the influence of a constant force

\mathbf{F} = (10\hat{\mathbf{i}} + 10\hat{\mathbf{j}} + 20\hat{\mathbf{k}})\,\text{N}

. The instantaneous power applied to the particle is (1)

200\,\text{W}

(2)

320\,\text{W}

(3)

140\,\text{W}

(4)

170\,\text{W}