P5: Forces and Energy Flashcards
Work
Energy transferred by a force.
Work(J) =
Force (N) x Distance moved in the direction of force (m)
What is needed for work to be done?
Energy
What is work done to overcome friction transferred as?
Energy that heats the objects that rub together and energy that heats the surroundings.
Power
The rate at which energy is transferred per second.
Watt
Power (W) =
Useful energy transferred (J) / Time taken
Gravitational Potential Energy
Energy of an object due to its position in a gravitational field.
When an object is moved up…
… Its GPE increases
GPE is equal to…
… The weight of an object
Change in GPE (J) =
Weight (N) x Change of height (m)
OR
Mass (kg) x GFS (N/kg) x Change in height (m)
Kinetic Energy (J) =
1/2 x mass (kg) x speed(2) (m/s(2))
Elastic Potential Energy
The energy stored in an elastic object when work is done on it.
What does the kinetic energy of an object depend on?
mass and speed
Kinetic Energy
The energy of a moving object due to its motion.