Lightning bolts occur when negative charges in clouds:

A. Flow positively to the ground
B. Flows negatively to the ground
C. Flows to the negatively charged clouds
D. cause thunder to sound

Complete these sentences. if a roller coaster train has a potential energy of 1,500 j and a kinetic energy of 500 j as it starts to travel downhill, its total energy isj. once the roller coaster train gets closer to the bottom of the hill, its kinetic energy increases to 1,100 j, and its potential energy decreases to j. when the train reaches the bottom of the track and is traveling along the ground, its kinetic energy isj.