A 70-kg boy is sitting 3 m from the ground in a tree. What is his gravitational potential energy

Several mountains together form a mountain . a few of these combined form a mountain system. several systems combined form a mountain , which can stretch thousands of miles in length.

Explain why electric current cannot exist if a current doesn't have a voltage source.

Amoving company collects data about couches they move and displays the data in a table. the force along the ramp, the angle of the ramp, and the height the couch is raised to are shown. which statements correctly compare the work done to move the couches? check all that apply. the same amount of work is done for couches 1 and 3. the same amount of work is done for couches 2 and 3. the work for couch 1 is greater than the work for couch 2. the work for couch 2 is less than the work for couch 3. the work for couch 3 is greater than the work for couch 1. the work for couch 2 is greater than the work for couch 1.