1. 6.4 Electrical Power and Potential Difference. Can you match these quantities to their units? CurrentOhms ResistanceCoulombs PowerAmps VoltageWatts ChargeVolts 05 December 2015

2. 6.4 Electrical Power and Potential Difference. Answers Current Amps Resistance Ohms Power Watts Voltage Volts Charge Coulombs 05 December 2015

3. 6.4 Electrical Power and p.d. The Power of an electrical device is the amount of energy it transfers every second. The Power depends on the current and potential difference (Voltage) 05 December 2015 In the USA the Voltage is 110V. What would happen if you plugged a UK device into this Voltage? What might happen if an American plugged their device into the UK mains? Page 190 AQA Physics

4. Power Power= Energy transferred (Joules, J) Time (seconds, s) (Watts, W) E.g A light bulb uses 6000J of energy in 1 minute. How powerful is the bulb? Power = ?Energy = 6000JTime = 1 minute = 60s Power = 6000 / 60 Power = 100 Watts Questions 1)An electric heater uses 3600000J in one hour. How much power does it use? 2)A car engine is rated at 100kW. How much energy does it use in 1s, 1min and 1 hour? Page 190 Question a)

5. A pacemaker controls the beat of the heart. These contain explosive materials. If a body is cremated the pacemaker will explode in the incinerator causing quite a bit of damage and a really loud bang – not what you’d want at a funeral! Electrical Power Power = Current x Potential Difference Watts, WAmperes, AVolts, V E.g. What power is used by a 12V, 5A car bulb? Power = 5A x 12V = 60 Watts Answer Question b) p191. Then Question 2 in the summary questions