© Oxford University Press 2011 IP Pairs of devices Pairs of devices

© Oxford University Press 2011 IP Pairs of devices Different types of electrical devices have advantages and disadvantages. Look at pairs of devices on the following screens and think of one advantage and one disadvantage for each of them.

© Oxford University Press 2011 IP Pairs of devices Battery-powered radio Wind-up radio

© Oxford University Press 2011 IP Pairs of devices AdvantageDisadvantage Battery- powered radio Will run on its own Batteries will need to be replaced Wind-up radio Costs nothing to run Need to wind it up regularly

© Oxford University Press 2011 IP Pairs of devices High power electric heater Low power tubular heater

© Oxford University Press 2011 IP Pairs of devices AdvantageDisadvantage High power electric heater Gives off more heat Not suitable for small spaces Low power tubular heater Can be installed in small spaces Generates only low background heat

© Oxford University Press 2011 IP Pairs of devices Standard light bulb Energy saving light bulb

© Oxford University Press 2011 IP Pairs of devices AdvantageDisadvantage Standard light bulb Cheaper to buyNot energy efficient Energy saving light bulb Less energy is wasted as heat More expensive to buy

© Oxford University Press 2011 IP Pairs of devices Electric oven Microwave oven

© Oxford University Press 2011 IP Pairs of devices AdvantageDisadvantage Electric oven More versatile for cooking Takes longer to cook Microwave oven Cooks quickly and uses less energy Can’t cook much in one go