Electricity Experiences and Outcomes

1. ElectricityExperiences and Outcomes Having measured the current and voltage in series and parallel circuits, I can design a circuit to show the advantages and disadvantages of parallel circuits in an everyday application. SCN3-09a I can help design simple chemical cells and use them to investigate the factors which affect the voltage produced. SCN3-10a

2. Learning Intentions • To explore what you know about electricity and find out something new about electricity • To understand how we generate some of our electricity • To understand the dangers of electricity

3. Lesson Starter In the back of your class jotter: • Write down all the times you have used electricity since waking up this morning.

4. What We Know Already • In your group: • Discuss what you already know and understand about electricity. For example, what facts, words and meanings do you know about electricity? • Write a summary of what you and your group have talked about in your jotter. You might use a mind map, bullet points or a table. • Share your summary with the rest of the class when everyone is ready.

5. In your jotter: • Write the heading “What We Know Already about Electricity” • Write three key points about electricity https://www.twigonglow.com/film/what-is-electricity-1540/

6. What is Electricity? • Electricity is a type of energy and we rely on it everyday. • Generating electricity is expensiveand we are trying to find cheaper and renewable ways of generating electricity. • http://www.educationscotland.gov.uk/weatherandclimatechange/energy/renewable/hydroelectric.asp

7. Renewable Energy • Scotland currently generates 41.6% of our electricity from renewable sources. • The Scottish Government wants to make this 100% by 2020! • In Iceland, 87% of their electricity comes from hydroelectricity! • 100% of Iceland's space heating and water heating is obtained from geothermal sources!

8. Electrical Safety • Electrical faults are one of the most common causes of fires in the home. • You should check your smoke alarms once every week and change the batteries once every year. • https://www.twigonglow.com/film/electrical-safety-1542/

9. Success Criteria • I found out something new about electricity • I understand how we generate some of our electricity • I understand the dangers of electricity

10. Lesson Starter • Name three appliances that use electricity. • Why do grown ups keep telling you to turn lights off when you’ve stopped using them. • How often should you check your smoke alarms? • What country is a world leader in renewable energy?

11. Conductors and insulators Learning intention • To understand the difference between conductors and insulators. • To be able to build circuits.

12. Conductors and insulators • Today, we will test a number of materials to see if they are conductors or insulators • What you will need: • Circuit board, 2 batteries, 1 bulb, 3 wires • 1 bag of insulators and conductors • Build a circuit that lights the bulb.

13. Conductors and insulators • Test each material • The bulb will light up if a current flows • Note the conductors and insulators in a table - - + + Test Material

14. Results Remember: It’s a conductor if the bulb lights, if not it’s an insulator!

15. Results

16. Conclusion A conductor allows electricity to pass through it. Examples: copper, iron, aluminium. An insulator does not allow electricity to pass through it. Example: rubber, glass, perspex.

17. Summary • A material which allows electricity to pass through it is a conductor • A material which does not allow electricity to pass through it is an insulator • All metals are conductors such as the copper wire inside an electric cable • Most non-metals are insulators such as the plastic cover on an electrical cable • Insulators are important because they prevent us from getting electrical shocks

18. Success Criteria • I can build working circuits. • I know the difference between conductors and insulators.

19. Lesson Starter • 1. What is a conductor? • 2. Give an example of a material that is a conductor. • 3. What is an insulator? • 4. Give an example of a material that is an insulator.

20. Learning intention • To be able to draw six different circuit symbols • To be able to draw a circuit diagram

21. Circuit symbolsDraw this table in your jotters

22. Rules for circuit diagrams • Always use a ruler. • Use circuit symbols only. • Circuit symbols are never drawn at the corners of circuit diagrams.

23. Circuit diagrams • Using two batteries and one bulb build a circuit that lights the bulb. • Draw the circuit diagram. • Using three batteries and two bulbs build a circuit that lights the bulb. • Draw the circuit diagram.

24. Circuit diagrams

25. Circuit diagrams • Using two batteries, one bulb and a switch build a circuit where the switch turns the bulb on and off. • Draw the circuit diagram. • Using three batteries, two bulb and a switch build a circuit where the switch turns the bulbs on and off. • Draw the circuit diagram.

26. Circuit diagrams

27. Success Criteria • Can draw the circuit symbols for 6 electrical components. • I can successfully draw a circuit diagram

28. Lesson Starter • Draw three circuit symbols. • Draw a circuit diagram with two batteries, a bulb and a switch, where the switch turns the bulb on and off.

29. Learning Intentions • To understand the definition of current. • To understand the defintion of voltage • To be able to draw and identify series circuits.

30. Current • Current is the flow of electrons (negative charges) or electricity round a circuit. • It is measured using an ammeter. • Current has the symbol I • It is measured in units called amperes or A

31. Voltage • Voltage is the energy given to each electron in a circuit. • We measure voltage using a voltmeter. • Voltage has the symbol V and it has units measured in volts or V.

32. Types of circuits • A circuit is an electrical path around which charge or electricity can flow (current). • There are two types of circuits: • Series • Parallel

33. Series Circuit • In a series circuit there is only one electrical path and all the components are connected in a chain or in a row. • A series circuit looks like this:

34. Series Circuit Summary • Two bulbs connected in series: • If you disconnect one bulb the other bulb goes out. • As you add more batteries the bulbs get brighter. • As you add more bulbs, the bulbs get dimmer. • When one bulb is disconnected, the other bulbs go off. • There is no other route for the electricity. • The charges (current) flows through every component.

35. Series Circuit • Build a series circuit with one battery and one bulb and draw in your jotter. • Add more batteries • Write down what happens. • Begin with one battery and one bulb again. • Add more bulbs • Write down what happens • Disconnect one of the bulbs. • Write down what happens.

36. Success Criteria • I understand the definition of current. • I understand the definition of voltage • I can draw and identify series circuits.

37. Lesson Starter • Draw a series circuit with one battery and two bulbs.

38. Learning Intention • To be able to draw and identify a parallel circuit.

39. Parallel Circuit • Build a circuit with one battery and one bulb. • What do you notice about the brightness of the bulb(s) when you add more bulbs in parallel? • What do you notice when you disconnect one of the bulbs?

40. Parallel Circuit • In a parallel circuit there is more than one electrical path. • The different paths for the electricity are known as branches.

41. Parallel Circuit • Two bulbs connected in parallel: • If you disconnect one bulb the other bulb stays lit. • Bulbs connected in parallel have the same brightness. • As you add more bulbs in parallel the brightness of each bulb does not change by much.

42. Parallel Circuit • Build a parallel circuit with one battery and one bulb. • What do you notice when you add more batteries? • What do you notice when you add more bulbs in parallel? • What do you notice when you disconnect one of the bulbs?

43. Parallel Circuit • Why do you think parallel circuits are useful in the home?

44. Success Criteria • I can draw and identify a parallel circuit.

45. ElectricityExperiences and Outcomes Having measured the current and voltage in series and parallel circuits, I can design a circuit to show the advantages and disadvantages of parallel circuits in an everyday application. SCN3-09a

46. Lesson Starter • Explain the difference between a series and parallel circuit.

47. Learning Intentions • To be able to draw series and parallel circuits using correct symbols.

48. Homework Complete homeworks 1 & 2 (homeworks are online) Due Wednesday 28th October.

49. Circuit Diagrams - Exercise 1 • Draw a series circuit with one battery and one bulb. • Draw a series circuit with two batteries, one bulb and a switch. • Draw a series circuit with three batteries, two bulbs and a switch.

50. Circuit Diagrams - Exercise 2 • Draw a parallel circuit with one battery and two bulbs (one bulb per branch) • Draw a parallel circuit with two batteries and three bulbs (2 bulbs on one branch and one bulb on the other) • Draw a parallel circuit with three batteries, three bulbs (one bulb in each branch) and switches that allow each bulb to be turned on and off separately.