Question

A motor boat is going in a river with a velocity $\vec{V}=(4\hat{i}-2\hat{j}+\hat{k})m{s}^{-1}$, If the resisting force due to stream is $\vec{F}=(5\hat{i}-10\hat{j}+6\hat{k})N,$ then the power of the motor boat is

• A. $100W$
• B. $50W$
• C. $46W$
• D. $23W$

Answer 1

Answer: (C)

$P=\vec{F}\cdot \vec{V}$