What is the acceleration of a sprinter if he increases his speed from 0 m/s in 0.5 seconds

Asap and show ! a 14 kg rock starting from rest free falls through a distance of 5.0 m with no air resistance. find the momentum change of the rock caused by its fall and the resulting change in the magnitude of earths velocity. earth mass is 6.0 * 10^24 kg. show your work assuming the rock earth system is closed.

By what primary heat transfer mechanism does the sun warm the earth?

Bonds within one water molecule are examples of