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प्रश्न
Define watt. Write down an equation linking watts, volts and amperes.
उत्तर
Watt is the unit of power. One watt can be defined as the power consumed by an electrical device if it is operated at a potential difference of 1 V and it carries a current of 1 A. That is:
1 watt = 1 volt x 1 ampere
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संबंधित प्रश्न
How many joules of electrical energy are transferred per second by a 6 V; 0.5 A lamp?
(a) 30 J/s
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(c) 0.83 J/s
(d) 3 J/s
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| Appliance | Current |
| Kettle | 8.5 A |
| Lamp | 0.4 A |
| toaster | 4.8 A |
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(c) ultraviolet rays
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