Work & Power Flashcards
What is meant by ‘work done’ in physics?
When a force causes an object to move energy is transferred and this is called work done.
How is work done related to energy transfer?
Work done is equal to the amount of energy transferred to the object.
What happens when you lift an object?
A force is applied and work is done to raise it to a higher position.
What type of energy increases when an object is lifted?
Gravitational potential energy increases.
What three factors affect gravitational potential energy?
The mass of the object the height it is raised to and the gravitational field strength.
Why does lifting an object require work?
Because a force must be applied to move it against gravity.
What happens to energy when an object falls?
Gravitational potential energy is transferred into kinetic energy.
What does the conservation of energy state?
Energy cannot be created or destroyed only converted from one form to another.
What energy change happens as a rollercoaster goes up a track?
It gains gravitational potential energy equal to the work done.
What energy change happens as a rollercoaster goes down?
Gravitational potential energy is converted into kinetic energy.
What happens to some of the energy during energy transfers?
Some energy is dissipated to the surroundings as thermal energy.
What type of energy does a moving object have?
Kinetic energy.
What two factors affect the amount of kinetic energy?
The mass of the object and its speed.
How does mass affect kinetic energy?
The greater the mass the more kinetic energy an object has.
How does speed affect kinetic energy?
The faster the object moves the more kinetic energy it has.
What is power in physics?
Power is a measure of how quickly work is being done.
What does power tell us about energy transfer?
It tells us how fast energy is transferred to an object.
