Question

Toy rocket of mass 0.1 kg has a small fuel of mass 0.02 kg which it burns in 3s. Starting from rest on the horizontal smooth track it gets a speed of 20m\s after the fuel is burned out. What is the thrust of the rocket?

Answer 1

Thrust exerted=0.8N.Thrust or force exerted by the burning fual on the rocket=mass*(final velocity-initial velocity)/(time in which the change in velocity take place).So, thrust=(.1+.02)*(20-0)/3=0.8kg.m/s^2