Question $5$

$10$ pts

Two blocks $(m1=40kg,m2=30kg)$ are connected by a compressed spring, and are initially at rest. The spring breaks and the two objects fly apart from one another. If the speed of the first block is $15\frac{m}{s},$ what is the speed of the second block?

$20\mathrm{.}0$ m$/$s

$15\mathrm{.}0\frac{m}{s}$

$11\mathrm{.}3\frac{m}{s}$

Cannot be determined.