Question

Ball A od mass 5.0 kilograms moving at 20. meters per second colides with ball B of imknnown mass moving at 10 meters per scond in the same direction. After the collision, ball A movies at 10. meters per second and ball B at 15 meters per second, both still in the same direction. What is the mass of ball B

Answer 1

10 kg

Step-by-step explanation:

Use law of conservation of momentum

momentum of system before collision = momentum of system after collision

5 kg * 20 m/s + x kg * 10 m/s = 5 kg * 10 m/s + x kg * 15 m/s

100 + 10x = 50 + 15 x

50 = 5x

x = 10 kg