A girl of mass $50\, kg$ jumps out of a moving boat of mass $300\, kg$ on to the bank with a horizontal velocity of $3\, m s ^{-1}$. With, what velocity, does the boat begin to move backwards ?
A girl of mass $50\, kg$ jumps out of a moving boat of mass $300\, kg$ on to the bank with a horizontal velocity of $3\, m s ^{-1}$. With, what velocity, does the boat begin to move backwards ?
Here, $m_{1}=50 kg , m_{2}=300 kg$
$v_{1}=3 m s ^{-1}$
$v_{2}=?$
$m_{1} v_{1}+m_{2} v_{2}=0$
$50 \times 3+300 \times v_{2}=0$
$300 v_{2}=-150$
$v_{2}=-\frac{150}{300}$
$=-0.5 m s ^{-1}$
Negative sign is for backward motion of the boat
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