Transferring Energy Flashcards
(15 cards)
What does the conservation of energy state?
Energy is never created or destroyed; it can only be stored, transferred, or dissipated.
What is a closed system?
A closed system is a collection of objects that can be treated completely on its own, without energy being exchanged with the surroundings.
How can you tell if a system is closed?
If the energy of a system increases or decreases, it is not closed.
Name the four main ways energy can be transferred between stores.
- Mechanically
- Electrically
- By heating
- By radiation
What does mechanical energy transfer involve?
A force acting on an object and doing work, such as pushing, stretching, or squashing.
How is energy transferred electrically?
By a charge doing work, such as charges moving around a circuit.
Describe energy transfer by heating.
Energy is transferred from a hotter object to a colder object.
What is energy transfer by radiation?
Energy transferred by waves, such as energy from the Sun reaching Earth by light.
In the example of a ball rolling up a slope, how is energy transferred?
Energy is transferred mechanically from the kinetic energy store of the ball to its gravitational potential energy store.
What happens when a bat hits a ball in terms of energy transfer?
Some energy is transferred mechanically to the ball’s kinetic energy store and some to the thermal energy stores of the bat and ball.
What occurs when a rock is dropped from a cliff?
Energy is transferred mechanically from the rock’s gravitational potential energy store to its kinetic energy store.
How does a car slow down without braking?
Energy in the kinetic energy store of the car is transferred mechanically to the thermal energy stores of the car and road due to friction.
How is energy transferred in a kettle boiling water?
Energy is transferred electrically from the mains to the heating element of the kettle, and then by heating to the thermal energy store of the water.
What do energy transfer diagrams represent?
Diagrams that show the energy transferred between stores and the work done against forces.
Fill in the blank: Energy cannot be _______.
[created or destroyed]
