PHYSICS HOMEWORK

My homework for efficiency in Physics, going to submit this knowt

What is useful energy?

energy intended on being produced

What is wasted energy?

all other non intended stores of energy

What is the energy input in a fan?

chemical

What is the useful energy out of a fan?

kinetic energy

What is the wasted energy out of a fan?

thermal energy

What is the energy input in a car?

chemical in fuel

What is the useful energy out of a car?

kinetic energy and thermal energy in the inside

What is the wasted energy out of a car?

thermal to surrounding

What is the energy input in a clock

chemical in the battery

What is the useful energy out of a clock?

kinetic energy from clock hands

What is the wasted energy out of a clock?

thermal energy to surroundings

Why are efficient devices better?

• better from the environment

• doesn’t waste as much thermal energy

• doesn’t need as much energy

• cheaper

How do you calculate efficiency?

efficiency = useful output energy transfer / total input energy transfer x 100%