If the force on a rocket moving with a velocity of 300 m/s is 210 N, then the rate of combustion of fuel is:
Correct answer: A. 0.7 kg/s
- A. 0.7 kg/s
- B. 1.4 kg/s
- C. 7 kg/s
- D. 10.7 kg/s
Explanation
The correct answer is 0.7 kg/s. The thrust force exerted by the rocket engine is given by the formula F = rate of fuel combustion × velocity of exhaust gases. Here, F = 210 N and velocity = 300 m/s. Solving for the rate of fuel combustion gives 210 N ÷ 300 m/s = 0.7 kg/s. Other options result from misapplying or miscalculating this formula.
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