Question

Alice launches a pendulum from a point that is a height h above the lowest point by giving the bob an initial velocity directed upward along the trajectory. Bob decides to launch the pendulum from the same position at the same speed but directed downward along the trajectory. Whose launch will cause the pendulum to reach a higher highest point? Briefly explain your answer.

Answer 1

Using the conservation of energy

where H is the maximum height, since both cases the initial speed is the same, then H is independent of the direction of the initial velocity.

Both bob will reach the same height