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प्रश्न
Name any two appliances which works on the phenomenon of heating effect of electric current.
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उत्तर
Fuse wire, electric iron, electric bulb, electric cooker, geyser.
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संबंधित प्रश्न
Why does the cord of an electric heater not glow while the heating element does?
Why is the tungsten used almost exclusively for filament of electric lamps?
How does the resistance of a wire vary with its area of cross-section?
Name any two effects of electric current.
The safety device based on the heating effect of electric current is called a ______.
An electric heater is connected to the 230 V mains supply. A current of 8 A flows through the heater.
(a) How much charge flows around the circuit each second?
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?
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?
Why does the connecting cord of an electric heater not glow hot while the heating element does?
Explain why, tungsten is used for making the filaments of electric bulbs.
Derive the expression for the heat produced due to a current 'I' flowing for a time interval 't' through a resistor 'R' having a potential difference 'V' across its ends. With which name is this relation known?
Give Scientific reasons.
In the electric equipment producing heat e.g. iron, electric heater, boiler, toaster etc, an alloy such as Nichrome is used, not pure metals.
Give Scientific reason.
In practice, the unit kWh is used for the measurement of electrical energy, rather than joule.
Heat energy is being produced in a resistance in a circuit at the rate of 100 W. The current of 3 A is flowing in the circuit. What must be the value of the resistance?
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.
Name any six domestic appliances based on the heating effect of electric current.
Answer the following question:
what is the heating effect of the electric current? state any four applications of it?
Which of the following substance contracts on heating?
What is the heating effect of electric current?
Write two devices based on the heating effect of electric current.
When does overloading occur?
Define fuse.
A current of 1 A is drawn by a filament of an electric bulb. Number of electrons passing through a cross-section of the filament in 16 seconds would be roughly:
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?
Three incandescent bulbs of 100 W each are connected in series in an electric circuit. In another circuit another set of three bulbs of the same wattage are connected in parallel to the same source.
- Will the bulb in the two circuits glow with the same brightness? Justify your answer.
- Now let one bulb in both the circuits get fused. Will the rest of the bulbs continue to glow in each circuit? Give reason.
(a) Observe the diagram given below and state whether the bulb will glow or not when we switch on K.
(b) Is it safe to handle the bulb when the switch is OFF?
(c) Give a reason for your answer in (b).
What is an electric fuse made up of?
What are the factors affecting heating effect of electric current?
______ wire is used in the filament of the bulbs.
Fuse is a strip of alloy wire which is made up of lead and tin with a very low ______.
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 |
Assertion: A current-carrying wire should be charged.
Reason: The current in a wire is due to the flow of free electrons in a definite direction.
The electric fuse works on the Joule heating principle.
Explain why fuse wire is always connected in a series arrangement.
What is the heating effect of electric current?
State the law that explains the heating effect of current with respect to the measurable properties in an electrical circuit.
