Machines can be made more efficient by reducing . mechanical energy

pressure

kinetic energy

friction

Apulley system is used to lift a 2,000 newton engine up a distance of 3 meters. the operator must apply a force of 250 newtons to the chain of the pulley system to lift the motor. to lift the engine 3 meters, the operator must pull a total of 30 meters of chain through the pulley system. what is the value of di?

Which changes would result in a decrease in the gravitational force btween two objects? check all that apply

The energy produced as a result of this flow of electrons from atom to atom is called