Question

A rocket of mass $1000kg$ is exhaust gases at a rate of $4{kgs}^{-1}$ with a velocity of $3000m{s}^{-1}$. The thrust developed on the rocket is

• A. $12000N$
• B. $120N$
• C. $800N$
• D. $200N$

Answer 1

The correct option is A

$12000N$

Step 1. Given Data,

Let $F$ is the Thrust Force of the rocket.

Mass $m=1000kg$

Exhaust rate $\frac{dm}{dt}=4{kgs}^{-1}$

Velocity $V=3000m{s}^{-1}$

Step 2. The thrust force developed on the rocket is,

We know that,

Thrust Force

$$\begin{gathered} F=V\times \left(\frac{dm}{dt}\right) \\ \Rightarrow F=3000m{s}^{-1}\times 4N \\ \Rightarrow F=12000N \end{gathered}$$

Therefore, the thrust force developed on the rocket is $F=12000N$.

Hence, the option A is correct.