A ball of mass 0.5kg moving at 10ms\(^{-1}\) collides with another ball of equal mass at rest. If the two balls move off together after the impact, calculate their common velocity.

A.

0.2ms\(^{-1}\)

B.

0.5ms\(^{-1}\)

C.

5.0ms\(^{-1}\)

D.

5.5ms\(^{-1}\)

Correct answer is C

Using; m\(_{1}\) u\(_{1}\) + m\(_{2}\) u\(_{2}\) = (m\(_{1}\) + m\(_{2}\))v

m\(_{1}\) = 0.5kg, u\(_{1}\) = 10ms\(^{1}\), m\(_{2}\) = 0.5kg, u\(_{1}\) = 0

\(\therefore\) (0.5kg x 10) + (0.5 x 0) = (0.5 + 0.5)v

v = 5ms\(^{1}\)