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प्रश्न
Unit of electric power may also be expressed as
विकल्प
volt ampere
kilowatt hour
watt second
joule second
उत्तर
volt ampere
Explanation -
Power is defined as
P = VI
where, V = Potential difference (Volt)
I = Current (Ampere)
So, unit of electric power may also be expressed as volt ampere.
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संबंधित प्रश्न
The atoms of copper contain electrons and the atoms of rubber also contain electrons. Then why does copper conduct electricity but rubber does not conduct electricity?
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State three factors on which the heat produced by an electric current depends. How does it depend on these factors?
An electric kettle has a heating element which is rated at 2 kW when connected to a 250 V electric supply. Calculate the
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(b) Resistance of the filament,
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has the larger working resistance?
| Appliances | Voltage (V) | Power (W) |
| (a) Washing machine | 250 | 3000 |
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| (c)240 | 240 | 1500 |
| ( d) Hair curler | 250 | 20 |
| ( e) Car head lamp | 12 | 36 |
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(ii) The heat energy produced in 1 minute.
What should I choose ___________________
b. for getting protection from electric current.
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