Please enable JavaScript.
Coggle requires JavaScript to display documents.
P1: Conservation and dissipation of energy - Coggle Diagram
P1: Conservation and dissipation of energy
1.3 Energy and work
Work done on an an object is when a force makes the object move
energy transferred = work done
Work done to overcome friction is transferred as thermal as the objects rub together
1.7 Energy and efficiency
efficiency [%] = (useful energy / total energy) x 100
energy wasted due to friction, air resistance, noise, electrical resistance
no energy efficiency is 100%
machines made more efficient by using lube
1.4 G.P.E stores
GPE store increases when it moves up (decreases when it goes down) as when it is lifted work is done to overcome the gravitational force
gravity is weaker on the moon
1,9 Energy and power
power is rate of transfer of energy
power wasted = total power input - useful power output
1.1 Changes in energy stores
energy is transferred by heating, waves, electric current, or a force
as object falls, gpe decreases and ke increases
if object doesnt bounce back, most of the ke is transferred into its surroundings like into heat or sound
1.8 Electrical appliances
electricity, gas/oil are main energy supply
electrical appliance is designed for a specific purpose and should aim to use as little energy as possible
1.2 Conservation of energy
Energy cant be created or destroyed
closed systems are systems in which no energy transfers out or into another another
1.6 Energy dissipation
useful energy is the energy in the place we want it and the form we need it in
wasted energy is the energy that is not useful and is transferred in an undesirable way
the more energy dissipates (spreads out) it becomes less useful
1.5 K.E and elastic energy stores
KE is the store energy of a moving object
Elastic energy is the energy stored in an elastic object