A 9800 kg rocket is travelling east along a horizontal fricitonless rail at a velocity of 11 m/s. The rocket is then accelerated uniformly to avelocity of 22 m/s in a time of 0.75 s by the expulsion of hot gases. What is the average force with which the gases are expelled by the rocket?

F = m x a

Plug in the values, find acceleration and plug that in for a.
F = 9800 * a
Solve for F.

To find the average force with which the gases are expelled by the rocket, we can use Newton's second law of motion, which states that force is equal to mass multiplied by acceleration (F = m * a).

Given:
Mass of the rocket (m) = 9800 kg
Initial velocity of the rocket (u) = 11 m/s
Final velocity of the rocket (v) = 22 m/s
Time taken to accelerate (t) = 0.75 s

First, we need to find the acceleration (a) of the rocket. We can use the formula:
a = (v - u) / t

Substituting the given values, we have:
a = (22 m/s - 11 m/s) / 0.75 s
a = 11 m/s / 0.75 s
a ≈ 14.67 m/s^2

Now that we have the acceleration, we can calculate the average force (F) using Newton's second law:
F = m * a

Substituting the given mass of the rocket, we have:
F = 9800 kg * 14.67 m/s^2
F ≈ 143,916 N

Therefore, the average force with which the gases are expelled by the rocket is approximately 143,916 Newtons.