Study Guide 8, Self Test 2
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1. A heater is designed to consume 1000 watts at 220 V. What current will it draw? If connected to a 110 V source, what will be the new power consumption and current?

2. If energy costs 8 cents per killowatt-hour, what will be the cost to run the heater in the previous problem at 220 V for a week?

3. It requires 3.35X105 J to heat 1 litre of water from 20º to the boiling point. If you heat the water in a 1000 W electric kettle which is 100% efficient:
(a) how long will it take to bring the water to the boiling point?
(b) at 8 cents per kW-hr, how much will it cost?

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