Chapter 7, Problem 5P

To determine

Force exerted on the rocket.

Answer to Problem 5P

Force exerted on the rocket is $F=6\times {10}^7\text{N}$

Explanation of Solution

Given:

Propelling gases expelled at a rate, $\frac{\Delta m}{\Delta t}=1500\text{kg/s}$

Speed, $v=4\times {10}^4\text{m/s}$

Formula Used:

Force exerted on the rocket is

  $F=v\frac{\Delta m}{\Delta t}$

Where, v is speed of gases and

  $\frac{\Delta m}{\Delta t}$ is rate at which propelling gases are expelled.

On substituting the given values, force exerted is

  $\begin{array}{l}F=\left(4\times {10}^4\text{m/s}\right)\left(1500\text{kg/s}\right)\\ \Rightarrow F=6\times {10}^7\text{N}\end{array}$

Conclusion:

Therefore, force exerted on the rocket is $F=6\times {10}^7\text{N}$