Question 6
Newton's Laws and MomentumA rocket burns fuel at the rate of 10 kg s−1 and ejects it with a velocity of 5 × 103 m s−1. The thrust exerted by the gas on the rocket is
- A.2.5 × 107 N
- B.5.0 × 104 N
- C.5.0 × 102 N
- D.2.0 × 10−3 N
Show the answer and explanation
Answer: B (5.0 × 104 N)
Explanation
Thrust = rate of change of momentum = (mass per second) × velocity = 10 × 5 × 103 = 5.0 × 104 N.