Question

Shelly rolls ball A in the positive x direction with a velocity of 7.5 meters/second. It hits stationary ball B and they undergo elastic collision. The two balls have different masses. Which of the following statements is true?

Answer 1

the sum of their y–momentums must be equal to zero

Step-by-step explanation:

Answer 2

If Shelly rolls ball A in the positive x direction with a velocity of 7.5 meters/second, and It hits stationary ball B and they undergo elastic collision, thus the two balls have different masses, then the following statement which is true is the statement that stated that there was no y-momentum initially.