What Is the west component of 85 m 25 north of west

Aboy with a mass 25 kg climbs into a small tree. he sits on a branch that is 2.o m above to the ground. what is his gravitational potential energy above the ground?

Consider a system with two masses that are moving away from each other. why will the kinetic energy differ if the frame of reference is a stationary observer or one of the masses?

Scientific models are based on current knowledge, which can limit their effectiveness when new discoveries are made.