Billiard ball A (0.35 kg) is struck such that it moves at 10 m/s toward a second identical ball (Ball B). After the collision Ball A continues to move

in the same direction at 2 m/s. What is the magnitude of the velocity for

Ball B after the collision?

Before Collision:

10 m/s

A

After Collision:

2 m/s

O

6m/s

Explanation:

Using the law of conservation of momentum which States that the sum of momentum of bodies before collision is equal to the momentum after collision.

Using the expression

m1u1 + m2u2 = (m1+m2)v

m1 and m2 are the masses

u1 and u2 are the initial velocities

v is the final velocity after collision

Substitute the given values in the formula

0.35(10)+0.35(2) = (0.35+0.35)v

3.5+0.7 = 0.7v

4.2 = 0.7v

v = 4.2/0.7

v = 6m/s

Hence the magnitude of the velocity for Ball B after the collision is 6m/s

d₁ = displacement of tern from arctic to antarctic = 11000 miles

d₂ = displacement of tern from antarctic to arctic =   - 11000 miles

d = total displacement for the journey

total displacement for the journey is given as

d = d₁ + d₂

d = 11000 + (-11000)

d = 0 miles

t₁ = time of travel from arctic to antarctic = 3 months = 3 x 30 days = 90 days

t₂ = time of travel from antarctic to arctic = 3 months = 3 x 30 days = 90 days

t = total time of travel

total time of travel is given as

t = t₁ + t₂

t = 90 + 90

t = 180 days

average velocity is given as

average velocity = total displacement/ total time

v = d/t

v = 0/180

v = 0 miles/day