A ball is thrown at an angle above the horizontal from the top of a cliff and feels no air resistance.A runner at the base of the cliff moves horizontally so that she is always under the ball.In this runner's reference frame,the path of the ball is a straight line rather than a parabola.

Question

Quizplus · Accepted Answer

In the runner's reference frame, the ball appears to move horizontally along with the runner. As such, the path of the ball appears to be a straight line rather than a parabola. This is because the vertical motion of the ball is cancelled out by the horizontal motion of the runner. However, in reality, the ball is still following a parabolic path relative to the ground.

A Ball Is Thrown at an Angle Above the Horizontal