P1.1 - P1.7 Flashcards
9 energy stores
nuclear- stored in the nucleus of an atom
magnetic- had by a magnetic object when near a magnet/magnetic field
electrostatic- energy a charged object has when near another charged object
how can energy be transferred
falling object energy transfers
conservation of energy
energy cannot be created or destroyed.
bungee jumping energy transfers
work done
force x distance (= energy transferred)
what happens to work done when overcoming friction (+ example)
how much force is needed to lift an object at constant velocity
GPE formula
weight (m x g) x height
why does GPE increase when object moves up (and by how much)
KE formula
1/2 x mass x speed2
elastic PE formula (+ units)
hookes law
F = ke
useful vs wasted energy
energy transfered to where it is wanted in the way that it is wanted vs not that
what happens to wasted energy
dissipated (spread out) and stored in less useful ways
what eventually happens to all useful energy
transferred to thermal energy store of surroundings
what happens to energy as it spreads out
energy efficiency
improving energy efficiency
closed system
total energy doesnt change - no energy can escape or enter
exam question!
energy transfers when stretching a spring
your chemical -> spring’s elastic PE
