Energy

Question 1

What are the different types of energy(answer 11)?

Answer 1

Energy in measured in joules J of kilojoules KJ
* Thermal - This is the energy of an object due to its temperature.
* Kinetic - This is the energy possessed by a moving object. Kinetic energy increases as the object’s speed is increased.
* Gravitational potential energy - The gravitational potential energy of an object increases if it is raised upwards.
* Electrical potential energy- This is the energy transferred by an electric current
* Elastic potential energy - This is the energy stored in a stretched or squashed object
* Radiation
* Nuclear - This is energy that is released when nuclear reactions take place in the nucleus of an atom.
* Light - This is energy in the form of visible electromagnetic radiation
* Sound - This is energy in the form of a sound wave.
* Chemical energy - This is energy that is stored between the bonds inside molecules. sources of chemical energy include: fuel, food and batteries
* EM waves

Question 2

Where is our main source of energy

Answer 2

sun

Question 3

What is energy measured in?

Answer 3

J (joules) KJ(KiloJoules)

Question 4

How much is 1 calorie?

Answer 4

4200 joules

Question 5

What is the law of conservation of energy?

Answer 5

Energy cannot be created or destroyed. It can only be transformed from one form to another

Question 6

How many joules are required to lift 1kg up 1 metre

Answer 6

10J

Question 7

What is useful energy?

Answer 7

Useful energy is energy transferred to where it is required in the form that it is wanted

Question 8

What is wasted energy?

Answer 8

Wasted energy is energy that spreads out into the surroundings and is usually very complicated to reuse, which is usually heat.

Question 9

What is the formula for efficiency?

Answer 9

Efficiency=(useful energy output)/(total energy input)

Question 10

What is the percentage efficiency?

Answer 10

Efficiency *100

Question 11

practice Sankey diagrams

Question 12

What are the different heat transfers?

Answer 12

convection, conduction, radiation

Question 13

What is thermal conduction?

Answer 13

Thermal conduction is how thermal energy flows through a substance without the substance itself moving by the vibration of particles.

Question 14

What are the best conductors?

Answer 14

Solids and liquids and metals are the best at conducting, with non-metal gases being the worst.

Question 15

What is the name of a bad conductor?

Answer 15

insulator

Question 16

What are the two different ways heat can be transferred by conduction

Answer 16

From particle to particle, or, for metals, heat can also be transferred by the free delocalised electrons which is why metals are good conductors

Question 17

Why do clothes keep you warm?

Answer 17

Becasue air is insulated between the layers in the clothes to help retain warmth

Question 18

Why does less dense air rises

Answer 18

Gravity…

Question 19

What is convection

Answer 19

Convection is the transfer of heat through fluids (liquids and gases) by the upward movement of warmer, less dense regions of fluid.

Question 20

In what direction does heat flow?

Answer 20

From areas of higher heat to lower heat

Question 21

Where does convection and conduction not happen?

Answer 21

In a vacuum

Question 22

land breeze sea breeze