Y8 Electricity 04 resistance
Transcript of Y8 Electricity 04 resistance
Resistance
Learning Objective:• To describe the effect
of resistance on current in a circuit.
Starter:• What do you think will
happen to the flow of water as it passes the squeeze in the pipe?
water
Write your own definitions for Conductors & Insulators
Conductors • These materials allow
electricity to flow easily. We use these materials in electrical circuits.
Insulators • Insulators don't allow
electricity to flow easily and we use these materials to protect ourselves.
Video
Predict which items will conduct electricity
Metals Non-MetalsConductors Insulators
Check your predictions
How will you know which items conduct electricity?
Conductivity of different items
Will the lamp light up when the circuit is switched on?
Metals conduct electricity. Non-metals generally do not conduct
electricity.
Question:
• Is there anything in conductors and insulators which lets a current through?
• In a conductor, electric current can flow freely, in an insulator it cannot.
Why can metals conduct electricity?
Varying resistance
• Resistance can be changed by altering the length or shape of a conductor, and also by changing the material itself.
• Varying resistance turns out to be an amazingly useful thing to do. We can use it to control currents that in turn make things move faster, appear brighter, or sound louder.
Exit Ticket
• Write an exit ticket explaining one way that what you learned today could help you in the real world.
Resistance
Learning Objective:• To describe the effect of resistance on
current in a circuit.