This apparatus is used for demonstrating the law of conservation of momentum and energy. The Collision in two dimensions apparatus performs by holding a ball at the top of a curved track and then the ball is released, it travels down the inclined track and collides with another 4 balls placed on base track. It is observed that after the collision only one ball comes out of track. The apparatus comprises of a curved inclined metal track & 5 steel balls. The track is level so collision occurs only in the horizontal plane.