A 4,500-kg roller coaster cart has a speed of 5.00 m/sm/s when it reaches its first peak at a 95.5 mm height from the ground level. After descending, it climbs up the second hill which is 81.2 mm above the ground level. How fast is the roller coaster cart at the top of the second hill? Assume there is no friction with the rails and no air resistance during the cart's motion.

Apebble is thrown into a calm lake, ripples are formed from the center and move outward. the water particles in the lake travel in a circular pattern that moves up and down on the surface of a lake, and the energy travels a) diagonally. b) downward. c) horizontally. d) upward.

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?

Frequency of electromagnetic waves that a radio station is assigned is called