Question

question no 7 . please

Answer 1

Force of thrust on a rocket = u (relative) * Rate of ejection of fuel

(You can find the derivation of this formula in books like HCVerma)

So, Force of thrust = 100 * 2
Acceleration * Mass of rocket = 100 * 2
Acceleration * 100 = 100 *2
Acceleration of the rocket = 2 m/s^2

Now, Acceleration relative to ground
= g-a = 10 - 2 = 8 m/s^2

Hence, option D is correct answer.
Hope this helps you !!

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