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A rocket of initial mass m0 has a mass m...

A rocket of initial mass `m_0` has a mass `m_0(1-t//3)` at time t. The rocket is lauched from rest vertically upwards under gravity and expels burnt fuel at a speed u relative to the rocket vertically downward. Find the speed of rocket at `t=1`.

Text Solution

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The correct Answer is:
B, C
`(-(dm)/(dt))=m_0/3`
At `t=1`, mass will remain,
`m=m_0-m_0/3=2/3m_0`
Now using the equation,
`v=u-"gt"+v_r1n(m_0/m)`
`=0-g(1)+u1n((m_0)/(2//3m_0))`
`=u1n(3/2)-g`
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