Energy

Question 1

Name the 8 energy stores

Answer 1

Thermal energy
Kinetic energy
Gravitational potential energy
Elastic potential energy
Chemical energy
Nuclear energy
Light energy
Electrostatic energy
Sound energy

Question 2

How is energy transferred?

Answer 2

Energy is transferred mechanically (by a force doing work) electrically (work done by moving charges) by heating or radiation.

For example light or sound

Question 3

What is meant by system?

Answer 3

A system is an object or a group of objects

Question 4

What happens when a system changes

Answer 4

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.

Question 5

What are closed systems?

Answer 5

It can exchange energy but not matter to or from its surroundings

Question 6

What is the net change in the total energy of a closed system?

Answer 6

It is always zero

Question 7

What’s another way of saying energy transferred?

Answer 7

Work done

Question 8

What is meant by an open system?

Answer 8

It allows the exchange of energy and matter to and from its surroundings

Question 9

What is meant by an isolated system

Answer 9

It does not allow the transfer of matter or energy to or from its surroundings

Question 10

What is power defined as

Answer 10

Power is defined as the rate at which energy is transferred, or the rate at which work is done

Question 11

Energy can be transferred, usefully, stored or dissipated, but cannot…

Answer 11

Cannot be created or destroyed

Question 12

What happens when you stretch a spring

Answer 12

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

Question 13

The energy transfer of 1 joule per second is equal to a power of

Answer 13

1 watt

Question 14

What is Kinetic energy

Answer 14

The energy stored in moving objects (stationary objects have no kinetic energy)

Question 15

What is elastic potential energy

Answer 15

When we stretch a spring we’re applying a force to change the length of the spring (This is called doing “work”)

Question 16

What is the specific heat capacity of a substance

Answer 16

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

Question 17

The higher the thermal conductivity of a material what happens to the energy transferred

Answer 17

the higher the rate of energy transferred by conduction across the material

Question 18

What is meant by renewable energy source

Answer 18

A renewable energy source is one that can be renewed as it is used and it will never run out

Question 19

Name some uses of energy source

Answer 19

The uses of energy source includes:

transport
electricity
generation
heating

Question 20

What is gravitational potential energy

Answer 20

The energy stored in an object due to its position above the Earth surface

Question 21

What is thermal energy

Answer 21

The energy stored due to the objects temperature

Question 22

What is the law of conservation of energy

Answer 22

Energy can be transferred usefully, stored but cannot be created or stored

Question 23

Define work

Answer 23

Work is done whenever energy is transferred from one store to another

Question 24

Name two types of work

Answer 24

Mechanical work involves using a force to move an object

Electrical work involves a current transferring energy