General overview (energy - forces doing work)

What happens when there are energy transfers in a closed system?

There is no net change to the total energy in the system

How can energy in a system be changed?

Through work done by forces, in electrical equipment, in heating

Energy transferred is equal to…

Work done

Formula for work done

E=f x d

Energy=force x distance

Formula For GPE

GPE=mass x gravitational field strength x height

Formula for KE

KE=1/2 x mass x velocity²

How is energy dissipated?

Usually as thermal energy to the surroundings

When do mechanical processes become wasteful?

When they cause a rise in temperature, so energy dissipates by heating the surroundings

Formula for power

Power=energy/temperature

What is a watt?

Joules per second

Formula for effiency

Efficiency=useful energy/total energy

What is power?

The rate at which energy is transferred