Question

Ball 1 with a mass of 10 kg, is moving to the right at 20 m/s. Ball 2 is moving to the left at 20 m/s. Upon collision Ball 2 comes to a standstill, while Ball 1 moves to the left at twice it’s original speed. What is the mass of Ball 2?

Answer 1

Since this is worded like an elastic collision:
\[m_1v_1+m_2v_2=m_1v_1'+ m_2v_2'\]\[(10kg)(20m/s)+m_2(20m/s)=(10kg)(0m/s)+m_2(40m/s)\]Now you just need to solve for m2 :)

Answer 2

The above is based on the Law of Conservation of Momentum btw. Momentum is conserved in both elastic and inelastic collisions (as opposed to kinetic energy which is only conserved in elastic collisions).

Answer 3

Alright, thank you.

Answer 4

Np...you should get an answer of m2=10kg

Answer 5

Alright..O: Thank you tons!