Question

A 2kg object is moving at 14m/s colloides with another object of 5kg at rst sticks to it ind te speed of the combination

Answer 1

$obj1) \\ m = 2kg \: \: u = 14m|s \\ p1 = mu \\ = 2 \times 14 = 28kg.m|s \\ \\ obj2) \\ m = 5kg \\ u = 0 \: m|s \\ p2 = mu \\ = 5 \times 0 = 0kg.m|s \\ momenta1 = p2 + p1 = 28kg.m|s \\ \\ after \: collision) \\ m = 2 + 5 = 7kg \\ v = x \\ p = mv = 7x \: kg.m|s \\ \\ p = momenta1 \: (law \: of \: conservation \: of \: momentum) \\ 7x = 28 \\ x = \frac{28}{7} = 4m|s$