Question

A red 8-kg ball that is going 3-m/s collides with a 2-kg blue ball that is at rest. The blue

ball then goes 6-m/s. What is the red ball's speed?

Answer 1

Step-by-step explanation:

Given:

m₁ = 8 kg

V₁ = 3 m/s

m₂ = 2kg

V₂ = 0

V₂' = 6 m/s

__________

V₁' - ?

m₁V₁ + m₂V₂ = m₁V₁' + m₂V₂'

8·3 + 2·0 = 8·V₁' + 2·6

24 = 8·V₁' + 12

24 - 12 = 8·V₁'

12 = 8·V₁'

V₁' = 12 / 8 = 1.5 m/s