energy: forces doing work Flashcards
1
Q
energy can never be …
it can only be …
A
energy can never be created or destroyed
it can only be transferred
2
Q
what is a closed system?
A
a system which experiences no external forces e.g. circuit
3
Q
in a motor, what does electrical energy change into?
A
kinetic energy
4
Q
what is work done?
A
an external force transferring energy onto something
5
Q
why are mechanical processes wasteful when they get hot?
A
due to friction
