Answer: 10 m/s
Step-by-step explanation:
Given
Momentum of boy [tex]P=200\ kg.m/s[/tex]
Mass of boy is [tex]m=20\ kg[/tex]
Momentum is the product of mass and velocity
[tex]P=mv[/tex]
Substitute value
[tex]\Rightarrow 200=20\times v\\\Rightarrow v=10\ m/s[/tex]
Thus, the boy is moving with a velocity of 10 m/s
