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प्रश्न
What does overloading cause?
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उत्तर
Due to overloading, fuse wire melts and the supply gets shut down.
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संबंधित प्रश्न
Why does the cord of an electric heater not glow while the heating element does?
The safety device based on the heating effect of electric current is called a ______.
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(b) How much energy is transferred to the heater each second?
An electric room heater draws a current of 2.4 A from the 120 V supply line. What current will this room heater draw when connected to 240 V supply line?
Give two reasons why nichrome alloy is used for making the heating elements of electrical appliances.
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diameter?
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(a) magnitude of resistance of the resistor
(b) temperature of the resistor
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(d) time for which current is passed
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(a) thin and short
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(c) low melting point
(d) higher resistance than rest of wiring
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Statement 2 : Heat in the resistor is created according to the rule of energy conservation.
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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.
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what is the heating effect of the electric current? state any four applications of it?
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SFEU
Your teacher has shown you the following activity.
Activity: Teacher has wound a long insulated piece of wire around an iron nail in the form of a coil. Free ends of the wire are connected to a cell through a switch as shown in the following figure. The current is switched on and some pins are placed near the ends of the nail.
Write down any three questions that come to your mind about this activity.
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| A | B | C | D |
 |
 |
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Write an expression for the amount of heat produced in a resistor when an electric current is passed through it stating the meanings of the symbols used.
State the law that explains the heating effect of current with respect to the measurable properties in an electrical circuit.
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