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प्रश्न
When does overloading occur?
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उत्तर
Overloading occurs, when more appliances work together in a circuit.
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संबंधित प्रश्न
Why does the cord of an electric heater not glow while the heating element does?
An electric iron of resistance 20 Ω takes a current of 5 A. Calculate the heat developed in 30 s.
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(c) nichrome
(d) argon
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An electric iron of 1100 W is operated for 2 hrs daily. What will be the electrical consumption expenses for that in the month of April? (The electric company charges Rs 5 per unit of energy).
Statement 1 : Electric current ( flow of electrons ) creates heat in the resistor.
Statement 2 : Heat in the resistor is created according to the rule of energy conservation.
Explain Statement 1 with the help of Statement 2.
Give scientific reason :
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Name the factors on which the heat produced in a wire depends when current is passed in it, and state how does it depend on the factors stated by you.
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what is the heating effect of the electric current? state any four applications of it?
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B1, B2 and B3 are three identical bulbs connected as shown in Figure. When all the three bulbs glow, a current of 3A is recorded by the ammeter A.
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- Will the heat produced in both cases be equal? Explain.
- Will the heat produced be the same if the wires taken by them are of equal lengths but of different thickness? Explain.
Match the following
| 1. | Bulb | a. | Conductor |
| 2. | Electroplating | b. |
Insulator |
| 3. | Pure water | c. | Heating effect of current |
| 4. | Salt solution | d. | Chemical effect of current |
An electric fuse is a wire made up of a material having ______ melting point.
A trip switch is a ______ safety device.
The electric fuse works on the Joule heating principle.
An electric kettle of 2 kW is used for 2h. Calculate the energy consumed in
- kilowatt hour and
- joules.
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