Two billiard balls are initially traveling toward each other at speeds of 1.90 m
ID: 2152829 • Letter: T
Question
Two billiard balls are initially traveling toward each other at speeds of 1.90 m/s for ball 1 and 3.80 m/s for ball 2. The balls undergo an elastic, head-on collision. Find their final velocities.
ball 1
What is the direction on ball 1?
in the same direction it was initially going
or
oppose the direction it was initially going
What is the direction on ball 2?
in the same direction it was initially going
or
oppose the direction it was initially going
Please explain...
magnitude 1 direction 2 ---Select--- in the same direction it was initially going. opposite the direction it was initially going.Explanation / Answer
Momentum conservation: m*1.9 - m*3.8 = m*v1 + m*v2
or v1 + v2 = -1.9............(1)
KE conservation: 1/2*m*1.9^2 + 1/2*m*3.8^2 = 1/2*m*v1^2 + 1/2*m*v2^2
or v1^2 + v2^2 = 18.05..........(2)
Solving (1) and (2), v1 = -3.8 m/s and v2 = 1.9 m/s
Hence, for ball 1, magnitude = 3.8 m/s, Direction = opposite