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प्रश्न
Answer the following question:
what is the heating effect of the electric current? state any four applications of it?
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उत्तर
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संबंधित प्रश्न
Name any two effects of electric current.
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?
What is nichrome? State its one use.
Give two reasons why nichrome alloy is used for making the heating elements of electrical appliances.
Write down the formula for the heat produced when a current I is passed through a resistor R for time t.
Explain why, tungsten is used for making the filaments of electric bulbs.
A resistance of 25 Ω is connected to a 12 V battery. Calculate the heat energy in joules generated per minute.
How much heat will an instrument of 12 W produce in one minute if it is connected to the heat produced by it?
The current passing through a room heater has been halved. What will happen to the heat produced by it?
Two exactly similar heating resistances are connected (i) in series, and (ii) in parallel, in two different circuits, one by one. If the same current is passed through both the combinations, is more heat obtained per minute when they are connected in series or when they are connected in parallel? Give reason for your answer.
Which electric heating device in your home do you think have resistors which control the flow of electricity?
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.
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.
Compute the heat generated while transferring 96000 coulombs of charge in two hours through a potential difference of 40 V.
These days when current in the circuit suddenly increases _______ switches are used.
A coil of an alloy _______ is used in electric heater cooker as a resistor.
Which of the following substance contracts on heating?
Which metal is used to make the filament of an electric bulb?
Write two devices based on the heating effect of electric current.
Name any two appliances which works on the phenomenon of heating effect of electric current.
When does overloading occur?
Define fuse.
Explain the heating effect of electric current.
Why is parallel arrangement used in domestic wiring?
B1, B2 and B3 are three identical bulbs connected as shown in Figure. When all the three bulbs glow, a current of 3A is recorded by the ammeter A.
- What happens to the glow of the other two bulbs when the bulb B1 gets fused?
- What happens to the reading of A1, A2, A3 and A when the bulb B2 gets fused?
- How much power is dissipated in the circuit when all the three bulbs glow together?
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.
Paheli took a wire of length 10 cm. Boojho took a wire of 5 cm of the same material and thickness. Both of them connected the wires as shown in the circuit given in the following figure. The current flowing in both the circuits is the same.
- Will the heat produced in both cases be equal? Explain.
- Will the heat produced be the same if the wires taken by them are of equal lengths but of different thickness? Explain.
An MCB can be used instead of a fuse in an electrical circuit.
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.
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.
What is a trip switch?
An electric fuse is a wire made up of a material having ______ melting point.
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?
