A rocket has a mass of 100 kg. 90% of this is fuel. It ejects fuel vap – McqOptions

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1.	A rocket has a mass of 100 kg. 90% of this is fuel. It ejects fuel vapours at the rate of 1 kg/sec with a velocity of 500 m/sec relative to the rocket. It is supposed that the rocket is outside the gravitational field. The initial upthrust on the rocket when it just starts moving upwards is [NCERT 1978]
A.	Zero
B.	500 N
C.	1000 N
D.	2000 N
Answer» C. 1000 N

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