Topic 1 - Energy Flashcards
(21 cards)
What are all the energy stores?
Thermal, kinetic, chemical, gravitational potential, elastic potential, nuclear, electrostatic, magnetic.
How is energy transferred between stores?
Mechanically, electrically, heating, radiation.
What is a system?
A single object or group of objects.
What happens when a system changes?
Energy is transferred in or out of system or between energy stores.
What happens to energy in a closed system?
None get in or out, net energy change is 0.
What happens to the temperature of something as there is more thermal energy?
Rises.
Energy is transferred by doing ___.
Work.
When is work done?
When there is current or when a force is applied.
What is the Kinetic Energy Formula (Joules)?
1/2 x mass (kg) x velocity^2 (m/s)
If something is moving, what energy store does it have?
Kinetic.
Use the formula (for kinetic energy) to suggest what happens to the kinetic energy of an object as the object accelerates.
Kinetic energy increases.
What is the Gravitational Potential Energy (Joules)?
Mass (kg) x Gravitational Field Strength (N/kg) x Height (m).
Why does lifting an object increase the gravitational potential energy?
Height increase.
What do falling objects do?
Falling objects transfer energy.
Where there is no air resistance and an object is falling, between which two energy stores is energy transferred?
Gravitational Potential to Kinetic.
Energy transferred to other stores in real life though as air resistance.
What is the elastic potential energy (Joules) formula?
Elastic Potential Energy (Joules) = 1/2 x Spring Constant (N/m) x Extension^2 (m)
What things can change elastic potential energy?
Stretching, squashing.
At what point do stretching and squashing no longer affect the elastic potential energy of an object?
When the limit of proportionality has been reached.
What is the formula for specific heat capacity?
Change in Thermal Energy (Joules) = Mass (kg) x Specific Heat Capacity (Joules/(kg * degrees Celsius) x Change in Temperature (degrees Celsius).
What is specific heat capacity?
Amount of energy needed to raise 1kg of a substance by 1 degree Celsius.
What are the specific safety precautions for the Specific Heat Capacity Practical?
None.
