Question

A force F=2i+j +9k, is applied on an object which moves from rest to a velocity of

v= 6i +3j +k. Determine the power using these two values

Answer 1

As we know,

$$P=<\textbf{F}\textbf{v}>=(2,1,9)(6,3,1)=\\ =2·6+1·3+9·1=24\text{ W}.$$