Physics Question:?

Question

A particle, starting from point 'A' is projected down a curved diagonal runway. (point A is located at the top of the runway). The runway then curves upwards at the bottom (causing the particle to fly straight up (verticle) - Point 'B'. When the particle is launched off part B, it reaches a height of 4.00m above the floor before falling back down. Ignoring friction and air resistance , find the speed of the particle at point A.

Note: Point A is located 3m off the floor.

Answer 1

This is a Kinetic/Potential energy quesiton.

At point A, the particle has a total energy of ½mv² + mgh, where h is 3 m.

At point B, the particle has no kinetic energy (it's vertical, but at the top of its travel), so the total energy is mgh (where h is now 4 m).

½mv² = mg(4-3)

v² = 9.8x2

v = about 4.4 m/s