Create Presentation
Download Presentation

Download Presentation
## Yr11 Electrical Power 13.8

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -

**Yr11 Electrical Power 13.8**Revision**Water flows in a river**Current = how much water flows in a certain time Current = the rate of flow of water**Charge flows in an electrical circuit**Current = how much charge flows in a certain time Current = the rate of flow of charge**Charge is given electrical energy by the power supply**The charge loses energy when it flows through components in the circuit. When it flows through a resistor it changes to heat energy.**The power of a device or component I how quickly it**transfers energy Put these 4 devices in order of increasing power**1. How much heat energy does a 3kW kettle produce in 2**minutes? P = 3,000W t = 120s So E.T. = P x t = 3,600,000J 2. An electric fire produces 500,000J of heat energy in 3 minutes. Calculate its power. 3. How long will it take a 2kW water heater to give 300,000J of heat energy to the water inside it?**A current of 0.5A flows through a 240V bulb. Calculate its**power. • C = 0.5A V = 240V • P = V x C = 240 x 0.5 = 120W 2. What current flows through a 60W, 240V bedside lamp? 3. Which of these fuses should be used inside its plug? 1A 5A 10A 15A 30A