Which of the following cannot provide energy to charge an elemental burst?

The percent efficiency of a machine can never be 100% (or greater), because in the real world some energy is always converted into a. heat b. work c. input force d. output force

The difference between a red shift and a blue shift has to do with wavelength frequency. t or f

Hey student studies gravity using objects that have the same mass which two objects have the greatest gravitational force acting between them a. 100kg 1.0m 100kg b. 100kg 2.0m 100kg c. 100kg 2.0m 100kg big d. 100kg big 3.0m 100kg big