What is the equation for work done?
E=Fd
work done= force x distance
(must be parallel, x cos theta if not)
What is work done measured in?
Joules J
What is the equation for GPE (Gravitational potential energy)
E= mgh
GPE= mass x grav fielf strength x height
What is the equation for Kinetic energy
E=1/2 mv^2
kinetic energy= 1/2 x mass x speed^2
If something falls, why don’t you need it’s mass to calculate its final speed, assuming ideal conditions?
1/2mv^2=mgh
1/2v^2=gh
If GPE at the top dos not equal KE at the bottom, where has the energy been lost?
Loat as work done against frictional forces (friction and air resistance)- increases thermal energy store of surroundings.
This energy can be used in E=Fd to find size of friction.
Why does braking distance quadruple if you double your speed?
e=1/2mv^2
What is the definition of internal energy?
The sum of kinetic energy and potential energy of an object/substance
What does distance/time equal
average speed