Formulas Flashcards
what is energy transferred equal to?
work done
formula for work done?
work done (J) = force (N) x distance moved (m)
formula for change in objects GPE store?
change in GPE store = weight (N) x (change in) height (m)
formula for change in GPE store?
mass (kg) x gravitational field strength (N/kg) x height (m)
formula for kinetic energy?
kinetic energy (J) = 1/2 x mass (kg) x speed, squared (m/s)
formula for elastic potential energy?
elastic potential energy = 1/2 x spring constant (N/m) x extension, squared (m)
what does ‘work’ mean?
to move an object with an applied force.
what does ‘useful energy’ mean?
energy that is transferred to where it is wanted in a usable form.
what does ‘wasted energy’ mean?
energy that is transferred to a place where it is not wanted, and isn’t used it a usable form.
what does ‘dissipated energy’ mean?
energy being spread out to the surroundings in a less useful form.
what is a system?
an object or group of objects
what is the conservation of energy?
energy cannot be created or destroyed - it can only be transferred between energy stores.
what is a closed system?
A system in which no energy is transferred between stores
formula for power?
energy transferred / time taken for energy to be transferred
formula for efficiency (power)?
useful power out / total power in (x100%)
