Answer: The momentum of the child and milk together is 58.125 kg.m/s
Explanation:
Momentum is defined as the product of object's mass and velocity.
Mathematically,
[tex]p=mv[/tex]
where, p = momentum
m = mass of the object
v = velocity of the object
In the given question, we are given that a child of mass 21.0 kg is carrying a gallon of milk having mass 2.25 kg and running with a velocity of 2.5 m/s. Hence, the momentum by both milk and child will be:
[tex]p=(m_{child}+m_{milk})v[/tex] ....(1)
Given:
[tex]m_{child}=21.0kg\\m_{milk}=2.25kg\\v=2.5m/s\\p=?kg.m/s[/tex]
Putting values in equation 1, we get:
[tex]p=(21+2.25)kg\times 2.5m/s=58.125kg.m/s[/tex]
Hence, the momentum of the child and milk together is 58.125 kg.m/s
