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प्रश्न
An Electric bulb is marked 100 W, 230 V. What current does it take?
उत्तर
Current flowing in bulb = i = `"P"/"V"`
`= 100/230 = 10/23 "A" = 0.435` A
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संबंधित प्रश्न
The table below shows the current in three different electrical appliances when connected to the 240 V mains supply:
| Appliance | Current |
| Kettle | 8.5 A |
| Lamp | 0.4 A |
| toaster | 4.8 A |
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- The lamp is connected to the main supply by using a thin, twin-cored cable consisting of live and natural wires. State two reasons why this cable should not be used for connecting the kettle to the mains supply.
- Calculate the power rating of the kettle when it is operated from the 240 V mains supply.
- A main takes the kettle abroad where the mains supply is 120 V. What is the current is the kettle when it is operated from the 120 V supply?
State and define the household unit of electricity.
Two lamps, one rated 220 V, 50 W and the other rated 220 V, 100 W, are connected in serieswith mains of 220 V. Explain why does the 50 W lamp consume more power
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(i) Explain, why the defelct ion occurs in the galvanometer.
(ii ) State whether th e current in the coil is cl ockwise or anticl ockwise
when viewed from the end P.
(iii ) State th e observation in G when the coil is moved away from north
pole N of the magnet keeping the magnet stationary.
(iv)State the observation in G when both the coil and the magnet are
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