Energy Flashcards
Name the 8 energy stores
Thermal energy
Kinetic energy
Gravitational potential energy
Elastic potential energy
Chemical energy
Nuclear energy
Light energy
Electrostatic energy
Sound energy
How is energy transferred?
Energy is transferred mechanically (by a force doing work) electrically (work done by moving charges) by heating or radiation.
For example light or sound
What is meant by system?
A system is an object or a group of objects
What happens when a system changes
The energy is transferred. It can be transferred into away form the system between different objects in the system, or between different types of energy sources.
What are closed systems?
It can exchange energy but not matter to or from its surroundings
What is the net change in the total energy of a closed system?
It is always zero
What’s another way of saying energy transferred?
Work done
What is meant by an open system?
It allows the exchange of energy and matter to and from its surroundings
What is meant by an isolated system
It does not allow the transfer of matter or energy to or from its surroundings
What is power defined as
Power is defined as the rate at which energy is transferred, or the rate at which work is done
Energy can be transferred, usefully, stored or dissipated, but cannot…
Cannot be created or destroyed
What happens when you stretch a spring
When we stretch a Spring were applying a force to change the length of the spring. (Applying force=work) We are putting energy to stretch the spring the spring then stores the energy that is called elastic potential energy
The energy transfer of 1 joule per second is equal to a power of
1 watt
What is Kinetic energy
The energy stored in moving objects (stationary objects have no kinetic energy)
What is elastic potential energy
When we stretch a spring we’re applying a force to change the length of the spring (This is called doing “work”)
What is the specific heat capacity of a substance
The specific heat capacity of a substance is the amount of energy required to raise the temperature of 1 kg of the substance by 1°C
The higher the thermal conductivity of a material what happens to the energy transferred
the higher the rate of energy transferred by conduction across the material
What is meant by renewable energy source
A renewable energy source is one that can be renewed as it is used and it will never run out
Name some uses of energy source
The uses of energy source includes:
transport
electricity
generation
heating
What is gravitational potential energy
The energy stored in an object due to its position above the Earth surface
What is thermal energy
The energy stored due to the objects temperature
What is the law of conservation of energy
Energy can be transferred usefully, stored but cannot be created or stored
Define work
Work is done whenever energy is transferred from one store to another
Name two types of work
Mechanical work involves using a force to move an object
Electrical work involves a current transferring energy
