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Question
Electrical appliances have voltage and power ratings as listed below. Which
has the larger working resistance?
| Appliances | Voltage (V) | Power (W) |
| (a) Washing machine | 250 | 3000 |
| ( b) Television | 240 | 160 |
| (c)240 | 240 | 1500 |
| ( d) Hair curler | 250 | 20 |
| ( e) Car head lamp | 12 | 36 |
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Solution
| Appliances | Voltage (V) | Power (W) | Resistance (R in 0 =V2/P) |
| (a) Washing machine | 250 | 3000 | 20.8 |
| ( b) Television | 240 | 160 | 360 |
| (c)240 | 240 | 1500 | 38.4 |
| ( d) Hair curler | 250 | 20 | 3125 |
| ( e) Car head lamp | 12 | 36 | 4 |
Therefore, hair curier has the largest working resistance
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