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प्रश्न
What is overloading?
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उत्तर
When consumption of electrical power is huge, excessive current is drawn from the transformer supplying the electricity, and if the capacity of the transformer is insufficient, its fuse wire melts and the supply gets shutdown. Such events as called as overloading.
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संबंधित प्रश्न
Compute the heat generated while transferring 96000 coulomb of charge in one hour through a potential difference of 50 V.
Why is the tungsten used almost exclusively for filament of electric lamps?
An electric heater is connected to the 230 V mains supply. A current of 8 A flows through the heater.
(b) How much energy is transferred to the heater each second?
What is nichrome? State its one use.
Give two reasons why nichrome alloy is used for making the heating elements of electrical appliances.
Why is a series arrangement not used for connecting domestic electrical appliances in a circuit?
Write down the formula for the heat produced when a current I is passed through a resistor R for time t.
Name the material which is used for making the filaments of an electric bulb.
An electric fuse works on the:
(a) chemical effect of current
(b) magnetic effect of current
(c) lighting effect of current
(d) heating effect of current
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| P | `6.84xx10^8`Ωm |
| Q | `1.70xx10^8`Ωm |
| R | ` 1.0xx10^15`Ωm |
| s | `11.0xx10^-7`Ωm |
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What property of the filament wire accounts for this difference?
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Identify the figure and give its use.
Answer the following question:
what is the heating effect of the electric current? state any four applications of it?
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A coil of an alloy _______ is used in electric heater cooker as a resistor.
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What is used to turn off the sudden increase in current in the electrical circuit of the house nowadays?
Right or wrong sentence.
Live wire and neutral wires have a 220 V potential difference.
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(c) Give a reason for your answer in (b).
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| 1. | Bulb | a. | Conductor |
| 2. | Electroplating | b. |
Insulator |
| 3. | Pure water | c. | Heating effect of current |
| 4. | Salt solution | d. | Chemical effect of current |
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| Student | Object | Mass of Object before Rusting in g |
Mass of the coated object in g |
| A | Nail | 3.0 | 3.15 |
| B | Thin plate | 6.0 | 6.33 |
What might be the reason for the varied observations of the two students?
An electric kettle of 2 kW is used for 2h. Calculate the energy consumed in
- kilowatt hour and
- joules.
State the law that explains the heating effect of current with respect to the measurable properties in an electrical circuit.
An electric iron of resistance 20 Ω draws a current of 5 A. The heat developed in the iron in 30 seconds is ______.
The graph of voltage vs current for four different materials is shown below.
Which of these four materials would be used for making filament of bulb?
