The acceleration in the rocket at any instant is proportional to the nth power of the velocity of the expelled gases. Where the value of n must be ?
Correct answer: B. 1
- A. -1
- B. 1
- C. 2
- D. -2
Explanation
Rocket thrust is proportional to the exhaust gas velocity through F = (dm/dt)ve, and acceleration is F/m, so acceleration is proportional to ve^1. Therefore n = 1, option b; option c results from incorrectly using kinetic energy, which depends on the square of velocity.
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