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प्रश्न
A coil of an alloy _______ is used in electric heater cooker as a resistor.
पर्याय
Stainless steel
Nichrome
Copper
Bronze
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उत्तर
A coil of an alloy nichrome is used in electric heater cooker as a resistor.
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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.
When current is switched ‘on’ in a room heater, it ______.
Give two reasons why nichrome alloy is used for making the heating elements of electrical appliances.
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An electric iron of resistance 20 ohms draws a current of 5 amperes. Calculate the heat produced in 30 seconds.
Explain why, tungsten is used for making the filaments of electric bulbs.
Explain why, the current that makes the heater element very hot, only slightly warms the connecting wires leading to the heater.
A resistance of 25 Ω is connected to a 12 V battery. Calculate the heat energy in joules generated per minute.
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If the current flowing through a fixed resistor is halved, the heat produced in it will become:
An electric iron is connected to the mains power supply of 220 V. When the electric iron is adjusted at 'minimum heating' it consumes a power of 360 W but at 'maximum heating' it takes a power of 840 W. Calculate the current and resistance in each case.
Give Scientific reason
In the electric equipment producing heat e.g. iron, electric heater, boiler, toaster etc, an alloy such as Nichrome is used, not pure metals.
Identify the figure and give its use.
Identify the figure and give its use.
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?
Write the mathematical expression for Joule’s law of heating.
What is a short circuit?
Write two devices based on the heating effect of electric current.
How can overloading be avoided?
Explain the application of heating effect of electric current in an electric bulb with a diagram.
Name some devices that run using heat effect of electric current
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An electric kettle consumes 1 kW of electric power when operated at 220 V. A fuse wire of what rating must be used for it?
An electric component used as a safety device is electric circuit is ______.
Unscramble the following words:
SFEU
What are the uses of electromagnets?
What are the factors affecting heating effect of electric current?
Explain the working of an electric fuse.
Copper wire offers very little ______ and does not get heated up quickly.
If 220 V potential difference is applied across an electric bulb, a current of 0.45 A flows in the bulb. What must be the power of the bulb?
An electric kettle of 2 kW is used for 2h. Calculate the energy consumed in
- kilowatt hour and
- joules.
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?
