Question

A 200 glider and a 600 g glider are coupled together and move along a frictionless air track at 50 cm/s. An explosive charge on one of the gliders separates them, causing the 200 g glider to stop. What is the subsequent velocity of the 600 g glider?

Answer 1

$(m_1+m_2)v=m_1\cdot 0+m_2u,$

$u=\frac{m_1+m_2}{m_2}v,$

$u=\frac{200+600}{600}\cdot 50\approx67~\frac{cm}{s}.$