Chapter 10.1, Problem 13PP

To determine

Force exerted by motor.

Answer to Problem 13PP

Force exerted by motor is $1.3\times {10}^5\text{N}$

Explanation of Solution

Given:

Power developed by motor is $P=65\text{kW}$

Distance covered by elevator is $d=17.5\text{m}$

Time taken is $t=35\text{s}$

Formula used:

Power developed can be obtained by:

  $P=\frac{W}{t}$ ….. (1)

Calculation:

As, $W=Fd$

Putting $W$ in (1)

So,

  $\begin{array}{l}P=\frac{Fd}{t}\\ \Rightarrow F=\frac{Pt}{d}\\ =\frac{65\times 1000\times 35}{17.5}\\ =1.3\times {10}^5\text{N}\end{array}$