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A rocket of mass 100 kg burns 0.1 kg of ...

A rocket of mass 100 kg burns 0.1 kg of fuel per sec. If velocity of exhaust gas is 1 km/sec, then it lifts with an acceleration of

A

`1000 ms^(-2)`

B

`100 ms^(-2)`

C

`10 ms^(-2)`

D

`1 ms^(-2)`

Text Solution

Verified by Experts

The correct Answer is:
D
`(dm)/(dt) = 0.1 kg//sec , v = 1 km // sec = 1000 m//s`
mv = constant
`rArr m (dv)/(dt) = - v(dm)/(dt) = 0 ` [as m `darr`]
`rArr (dv)/(dt) = (1000 xx 0.1)/(100) = 1m//s^(2)`.
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