Q. A force $\overrightarrow{F} = 2\widehat{i} + 2\widehat{j}$ N displaces a particle through $\overrightarrow{S} = 2\widehat{i} + 2\widehat{k}$ m in 16 s. The power developed by $\overrightarrow{F}$ is
A) $0.25\ J{\ s}^{- 1}$
B) $25\ J{\ s}^{- 1}$
C) $225\ J\ s^{- 1}$
D) $450\ J{\ s}^{- 1}$
Explanation
(a) $\overrightarrow{P} = \frac{\overrightarrow{F} \bullet \overrightarrow{S}}{t}$
$= \frac{\left( 2\widehat{i} + 2\widehat{j} \right) \bullet (2\widehat{i} + 2\widehat{k})}{16}Js^{- 1} = \frac{4}{16}Js^{- 1} = 0.25Js^{- 1}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.