a cracker of mass 100 g explodes into 2 equal mass . show that these 2 pieces of cracker flies inopposite direction
In a closed system (one that does not exchange any matter with the outside and is not acted on by outside forces) the total momentum P =const. P = M * V0, where M = 100 g, V0 = 0. So, P = 0. After the explosion, P = m1 * V1 + m2 * V2, where m1 = m2 = M / 2. (M / 2) * V1 + (M / 2) * V2 = 0 V1 + V2 = 0 V1 = - V2, so these 2 pieces of cracker should fly in opposite directions.