Energy Flashcards
What is chemical energy?
Energy stored by chemical bonds
Chemical potential energy is stored in batteries, petrol, coal and food.
What is elastic potential energy?
Energy stored when an object is compressed, stretched or twisted
Elastic potential energy can be stored by springs and rubber bands.
What is elecrical energy?
Energy that passes through an electric circuit
Electrical energy is related to the movement of electrons through an electric circuit.
What is energy?
The ability to do work
Energy comes in many different forms, such as kinetic, electrical, sound, heat and light.
What is energy efficiency?
A measure of how much of the input energy is useful energy
The efficiency of a device is the useful energy divided by the input energy, multiplied by 100.
What is energy transfer?
The passing of energy from one object or place to another
When a player kicks a football, kinetic energy is transferred from the player to the ball.
What is **energy transformation **?
The conversion of energy from one form to another
A solar panel transforms** light energy into electrical energy.**
What is a flow diagram?
A model that shows how energy is transferred and transformed
Flow diagrams **are visual models **that help us understand energy transfers and transformations.
What is **gravitational potential energy? **
Energy stored when an object is raised above the ground
Gravitational potential energy is stored when someone climbs up to a high diving board.
What is heat?
Energy that can be felt as warmth
Heat always transfers from a warmer object to a cooler one.
What is input energy?
Energy supplied to a device
The input energy of a laptop is the electrical energy used to power it.
What is a joule?
The standard unit of energy
One joule is the amount of energy needed to lift an apple by 1 metre.
What is a kilojoule?
A unit of energy equal to 1000 joules
The energy stored in food is often measured in kilojoules.
What is Kinetic energy?
Energy of movement
All moving objects have kinetic energy, including a running cheetah and a kicked ball.
What is light energy?
Energy that can be seen
Light bulbs transform electrical energy into light energy.
What is a linear relationship?
A relationship that produces a straight line on a graph
Kinetic energy and mass have a linear relationship. Doubling the mass of an object causes its kinetic energy to double.
What is mass?
The amount of matter in an object or substance
Mass is one variable that affects kinetic energy. The standard unit of mass is kilograms.
What is a model?
A representation of an object, process or system
Models may be physical objects, diagrams, computer programs or equations.
What is a non-linear relationship?
A relationship that does not produce a straight line on a graph
Kinetic energy and speed have a non-linear relationship because the line on the graph is curved.
What is output energy?
Energy that comes out of a device
The output energy of a laptop is in the form of light, heat and sound.
What is potential energy?
Energy that is stored
Energy can be stored in a variety of forms, including elastic, gravitational and chemical.
What is sound energy?
Energy that can be heard
When a wolf howls, vibrations in air spread outwards as sound waves.
What is** Speed?**
The rate at which an object changes position
Speed is one variable that affects kinetic energy. The standard unit of speed is metres per second.
What is themal energy?
A form of energy that can be transferred as heat
Even cold objects, such as ice, have some thermal energy.
What is total energy?
The sum of all forms of energy in a situation
The total energy of a skier is the sum of their kinetic energy and gravitational potential energy.
What is useful energy?
Output energy that is put to the intended use
The useful output energy from a laptop includes sound and light.
What is wasted energy?
**Output energy that is not put to the intended use
**
The waste output energy from a laptop is heat as it is not useful.
