Here we are applying the equation, Fr−mg=ma
From Newton's second law, Fr=dtdmvr⇒dtdmvr=mg+ma
Put the given values in the above equations,
⇒dtdm500=1000(10+20)⇒dtdm=60kgs−1.
The initial mass of a rocket is 1000kg. Calculate at what rate the fuel should be burnt so that the rocket is given an acceleration of, 20ms−2. The gases come out at a relative speed of 500ms−1, with respect to the rocket:
[Useg=10ms−2]
Held on 26 Aug 2021 · Verified 6 Jul 2026.
10kgs−1
60kgs−1
500kgs−1
6.0×102kgs−1
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