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प्रश्न
Explain the application of heating effect of electric current in an electric bulb with a diagram.
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उत्तर
- Electric bulb works on the principle of heating effect electric of current.
- The solenoid type coil of bulb has high resistivity and very high melting point.
- When current is passed through the bulb, solenoid type coil of bulb gets heated to high temperature (upto 3400 °C) and starts glowing.
संबंधित प्रश्न
State four most common electrical appliances based on heating effect of electric current. Why do we use finely heated platinum wire in surgery?
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Write down the formula for the heat produced when a current I is passed through a resistor R for time t.
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Name the material which is used for making the filaments of an electric bulb.
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- the total current taken from the supply
- the resistance of each heater and
- the energy supplied in kWh to the three heaters in 5 hours.
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Statement 2 : Heat in the resistor is created according to the rule of energy conservation.
Explain Statement 1 with the help of Statement 2.
Solve the following question.
Compute the heat generated while transferring 96000 coulombs of charge in two hours through a potential difference of 40 V.
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Write scientific reason.
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Mark the correct choice
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Write down any three questions that come to your mind about this activity.
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Explain the working of an electric fuse.
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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 |
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The electric fuse works on the Joule heating principle.
In which of the following applications of Iron, rusting will occur most? Support your answer with valid reason.
| A | B | C | D |
 |
 |
 |
 |
In a set up the students coated iron nails with zinc metal and noted that, iron nails coated with zinc prevents rusting. They also observed that zinc initially acts as a physical barrier, but an extra advantage of using zinc is that it continues to prevent rusting even if the layer of zinc is damaged. Name this process of rust prevention and give any two other methods to prevent rusting.
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