Energy transfer. How is energy changing?

Transcription

1 Energy transfer How is changing?

2 Can you identify all transfers? Crouching Tiger Hidden Dragon

3 Watch the video clip What happens to when it is used? What transfers are occurring? What changes can you think off? Fire Breathing

4 Aim To identify transfers To identify waste Key words Wasted Useful

5 The bigger picture Have you ever wondered? Where does all the come from? 04/09/2016 cgrahamphysics.com 2016

6 All our food comes from the Sun. How? Sometimes we eat things that eat things that grow So if we eat vegetables or meat, we can say that all of our food has come from the Sun

7 Energy from the Sun Animals, such as humans, need to eat to live, grow and reproduce... and we eat things that grow as a result of sunshine giving us this food chain. light (from the sun) chemical (stored) (in the plant) chemical (stored) (inside the animal)

8 Energy makes things happen! When things happen an change takes place. Electrical Heat and Light One of the most important forms of is electrical.

9 Electrical comes from... light in solar cells kinetic in dynamos chemical in the fossil fuels used in power stations chemical stored in batteries

10 Electrical helps move from one place to another Most power stations use fossil fuels to make electricity which is transmitted through cables which we can then use in our homes. stored chemical electrical light (or sound, movement or heat )

11 Electrical can change to... But each time some type of is created that is not useful light sound heat kinetic (movement)

12 Wasted Whenever is changed from one form to another, some is always wasted. Energy is usually wasted as: heat ; sound. All electrical devices produce a small amount of heat, which is normally wasted.

13 Wasted sound If you can hear a device that is not designed to make noise then is wasted as sound. Examples of devices that waste as sound include: car engine hairdryer washing machine jet engine

14 Wasted heat If a device gets warm and it is not designed to get warm then is wasted as heat. Examples of devices that waste as heat include: Car engine mobile phone charger television radio

15 Which type of is wasted?

16 What happens to wasted? Remember that cannot be created or destroyed. Wasted spreads out into the surroundings this is called dissipated. This dissipated is too spread out to do useful work and so cannot be re-used. This is why it is important to reduce the amount of that is wasted.

17 Can you name the transfer? Wasted: heat Wasted: sound and heat Wasted: transpiration? cgrahamphysics.com 2016

18 Can you draw the flow diagram? electrical light sound heat

19 electrical sound heat

20 What are the main transfers in a car engine? (Don t forget the wasted.) chemical kinetic sound heat

21 The runner transfers as movement but also in two other ways. What are they? chemical (stored) runner kinetic (movement) heat + + sound

22 When a match is struck, what is the from the chemicals in its head transferred into? What is useful and what isn t useful? chemical (stored) match heat light + + sound

23 10.3 Non-useful transfers When you switch a TV on, what does it transfer from electrical into? What is useful and what isn t useful? electrical TV heat light + + sound

24 Can you name this example? Example (try in your books in pencil) Energy Movie Girl in Human Slingshot.avi

25 Key words Wasted that has spread out into surroundings and cannot be reused. Energy that is not desired but a by product of transfer Useful that gives the desired outcome