1. Tardigrade
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  4. A man is running on horizontal road has half the kinetic energy of a boy of half of his mass. When man speeds, up by 1 m / s, then his KE becomes equal to KE of the boy, the original speed of the man is

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Q. A man is running on horizontal road has half the kinetic energy of a boy of half of his mass. When man speeds, up by $1\, m / s$, then his KE becomes equal to KE of the boy, the original speed of the man is

Work, Energy and Power

Solution:

According to problem
$K_{B}=2 K_{m}$
$\frac{1}{2} m_{B} v_{B}^{2}=2\left(\frac{1}{2} m_{m} v_{m}^{2}\right)$
$\frac{1}{2} m_{B} v_{B}^{2}=2\left(\frac{1}{2} m_{m}\left(v_{m}+1\right)^{2}\right)$
Solving
$v_{m}=\sqrt{2}+1\, m / s$