If somebody fell from a 2 floor house and didn't break any bones and just got bruises what would have had to break his fall?

Why does lightning travel from clouds to the ground?

Aspring is used to stop a 50-kg package which is moving down a 20º incline. the spring has a constant k = 30 kn/m and is held by cables so that it is initially compressed 50 mm. knowing that the velocity of the package is 2 m/s when it is 8 m from the spring and neglecting friction, determine the maximum additional deformation of the spring in bringing the package to rest.

A51 kg woman skis down a hill and her kinetic energy is 9.96e4 j. what is her speed?