Question

1. A 4-N force is used to move an object 2 m in 10 s. Which of the following is the power generated while moving the object?

Answer 1

Power is the work done per unit time. Therefore,

$\begin{gathered} p=\frac{w}{t} \\ \text{where} \\ w=\text{work done} \\ t=\text{time} \end{gathered}$

Therefore,

$\begin{gathered} \text{work done=fd} \\ f=force=4N \\ d=\text{displacement}=2m \\ t=2\sec s \\ p=\frac{fd}{t}=\frac{4\times2}{10}=\frac{8}{10}=0.8watts \end{gathered}$