Why laser action can not be accomplished without population inversion between atomic level?

11. you want to calculate the displacement of an object thrown over a bridge. using -10 m/s2 for acceleration due to gravity, what would be the total displacement of the object if it took 8 seconds before hitting the water?

This is the substance(s) formed in a chemical reaction.

Inside of a windmill or a dam is a that is used to transform one type of energy into electrical energy. a. motor b. generator c. transformer d. power pack