Question 2
In the trolley experiment, the trolley travelled further when the object was sent in faster, and further again when a heavier object was used. Which two factors does kinetic energy therefore depend on?
The right answer is the one marked above.
Its mass and its velocity. The distance the trolley runs measures the energy it received, so anything that sends the trolley further means the object arrived holding more energy.
Because both factors matter, any formula for kinetic energy has to contain both — which is exactly what ½ m v2 does.