What is the main cause of lightning?
Lightning happens when the negative charges (electrons) in the bottom of the cloud are attracted to the positive charges (protons) in the ground.
<START_INST>What is the main cause of lightning?<END_INST><START_CTX><END_CTX><START_A>Lightning happens when the negative charges (electrons) in the bottom of the cloud are attracted to the positive charges (protons) in the ground.<END_A>