Laws of Motion - Result Question 14
14. If the force on a rocket moving with a velocity of $300 m / sec$ is $345 N$, then the rate of combustion of the fuel, is
[1995]
(a) $0.55 kg / sec$
(b) $0.75 kg / sec$
(c) $1.15 kg / sec$
(d) $2.25 kg / sec$
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Answer:
Correct Answer: 14. (c)
Solution:
- (c) Velocity of the rocket $(u)=300 m / s$ and force $(F)=345 N$. According to Newton’s second law, thrust (force) $=$ Rate of change of linear momentum.
$\frac{F}{u}=(\frac{d m}{d t})=1.15 kg / sec$
