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प्रश्न
An Electric bulb is marked 100 W, 230 V. What how long would this lamp take to consume one unit of electricity?
उत्तर
Energy consumed in kWh = `("W" xx "Time in hour")/1000`
`= (100 xx "t"("in hr"))/1000`
If energy consumed in 1 kWh, then 1 = `(100 xx "t")/1000`
time required for consuming 1 kWh, t = 10 hour.
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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 |
- Which appliance has the greatest electrical resistance? How does the data show this?
- 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?
Name the physical quality which is measured in
(i) Kw (ii) kWh
An electric bulb is rated at 220 V, 100 W. (a) what is its resistance? (b) what safe current can be passed through it?
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resistances
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What is wrong with the circuit diagram (Fig. 34)? Carefully check the symbols and assign proper positive and negative signs to them.
Why is heating coil wound in the form of a helix in electric stove?
Which material is the calorimeter commonly made of? Give one reason for using this material.
What is the function of the split rings in a d.c. motor?
If a heater coil rated lkW, 220 V is connected in series with an electric bulb of 100 W, 220 V and are supplied 200V, power consumed by the bulb in this circuit is ______.
