Which best describes the purpose of a controlled experiment?

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.

Acalorimeter uses the principle that thermal energy flows from hotter material to colder material until both reach the same

Wavelength of 125 meters is moving at a speed of 10 m/s. what is it's frequency?