Question

The mass of our hero is 69.0 kg, and the mass of his physics book is 1.725 kg. What is the total momentum of the system of particles consisting of the book and our hero combined as they are slipping across the ice together BEFORE our hero throws his physics book?

Answer 1

Answer: The momentum of the combined system will be equals to P =
`(69 + 1.725) * V` i.e
`70.725 * V` Kg m/s

Explanation:

Mathematically momentum of a body is defined as mass times the velocity of that body.

It is a vector quantity, have magnitude as well direction and it is denoted by the notation "p"

The S.I. unit of momentum is Kg m/s.

`Momentum (p) = Mass (m) * Velocity (v)`

Momentum of hero (
`p_(1)`) =
`m_(1)* v_(1)` =
`69 * v_(1)`

Momentum of book (
`p_(2) = m_(2) * v_(2)` =
`1.725 * v_(2)`

If we consider both the hero and book as system that is moving with a common velocity i.e. V m/s then the momentum of the combined system will be equals to

P =
`(m_(1) + m_(2)) * V`

P =
`(69 + 1.725) * V`

P =
`70.725 * V` Kg m/s