Bell Work

1. What is the equation for resistance?2. What happens to the current if the

voltage is doubled?3. What happens to the current if the

voltage is doubled and the resistance is doubled?

4. What happens to the current if the voltage is doubled and the resistance is halved?

How is a teacher like a fuse?

P4.5 Electrical Safety

Lesson Objectives• To explain how

electrical devices are designed with protection in mind

Learning OutcomesGrade C• Describe and explain the

functions of a plugGrade B• Explain why double

insulated appliances are useful

Grade A• Describe and explain how

fuses workGrade A*• Explain why houses use a

combination of fuses and circuit breakers

What do you already know about today’s learning outcomes?

All appliances need Earthing?

Agree/disagree/why?

Fuses

• Why is this device useful?• What are the disadvantages?

• What?• Why?• When?

P4.5 Electrical Safety

Lesson Objectives• To explain how

electrical devices are designed with protection in mind

Learning OutcomesGrade C• Describe and explain the

functions of a plugGrade B• Explain why double

insulated appliances are useful

Grade A• Describe and explain how

fuses workGrade A*• Explain why houses use a

combination of fuses and circuit breakers

What do you already know about today’s learning outcomes?