A 8.0 kg box is released from rest on a frictionless ramp. The box slides from the ramp onto a rough horizontal surface with a friction mk =0.50. The starts at a height of 4 meters (yo = 4 m). What is the formula for force friction?

What is the formula for work (W)?

What type of energy does the box have at the begging on this problem?

Where does the energy go after the box come to rest?

What distance d will the box slide?

Do you agree with scientist’s prediction about the warming of alaska and other polar regions?

Electric field of the earth. the earth has a net electric charge that causes a field at points near its surface equal to 150 n> c and directed in toward the center of the earth. (a) what magnitude and sign of charge would a 60-kg human have to acquire to overcome his or her weight by the force exerted by the earth’s electric field? (b) what would be the force of repulsion between two people each with the charge calculated in part (a) and separated by a distance of 100 m? is use of the earth’s electric field a feasible means of flight? why or why not?

The law of the conservation of momentum says that the total momentum of any closed and isolated system cannot