Advertisements
Advertisements
प्रश्न
In an electric bulb, coil of _______ metal is used.
पर्याय
copper
tungsten
aluminium
iron
Advertisements
उत्तर
In an electric bulb, coil of tungsten metal is used.
APPEARS IN
संबंधित प्रश्न
Compute the heat generated while transferring 96000 coulomb of charge in one hour through a potential difference of 50 V.
An electric iron of resistance 20 Ω takes a current of 5 A. Calculate the heat developed in 30 s.
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.
The current passing through a room heater has been halved. What will happen to the heat produced by it?
Name the material which is used for making the filaments of an electric bulb.
The elements of electrical heating devices are usually made of:
(a) tungsten
(b) bronze
(c) nichrome
(d) argon
If the current flowing through a fixed resistor is halved, the heat produced in it will become:
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.
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.
Name any six domestic appliances based on the heating effect of electric current.
Rewrite the following statement by selecting the correct option:
1 A = ____________ mA.
Solve the following question.
Compute the heat generated while transferring 96000 coulombs of charge in two hours through a potential difference of 40 V.
A coil of an alloy _______ is used in electric heater cooker as a resistor.
What is the heating effect of electric current?
Live wire and neutral wires have a 220 V potential difference.
Write scientific reason.
A coil made up of alloy Nichrome is used in the electric heater cooker as a resistor.
When does overloading occur?
Which of the following is correct?
Assertion: Bending of wire decreases the resistance of the electric wire.
Reason: The resistance of a conductor depends on length, thickness, nature of material and temperature of the conductor.
Why is parallel arrangement used in domestic wiring?
What is Joule’s heating effect? How can it be demonstrated experimentally? List its four applications in daily life.
Name two electric devices for each where
- heating effect of current is used and
- magnetic effect of current is used.
What are the uses of electromagnets?
What are the factors affecting heating effect of electric current?
It would cost a man Rs. 3.50 to buy 1.0 kW h of electrical energy from the Main Electricity Board. His generator has a maximum power of 2.0 kW. The generator produces energy at this maximum power for 3 hours. Calculate how much it would cost to buy the same amount of energy from the Main Electricity Board.
______ wire is used in the filament of the bulbs.
Copper wire offers very little ______ and does not get heated up quickly.
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.
Name a few appliances which work on the basis of the heating effect of current.
A student boils water in an electric kettle for 20 minutes. Using the same mains supply he wants to reduce the boiling time of water. To do so should he increase or decrease the length of the heating element? Justify your answer.
What is a trip switch?
In the electric equipment producing heat like iron, electric heater, boiler, toaster etc., an alloy such as nichrome is used, not pure metals.
An electric kettle of 2 kW is used for 2h. Calculate the energy consumed in
- kilowatt hour and
- joules.
Anannya responded to the question: Why do electrical appliances with metallic bodies are connected to the mains through a three-pin plug, whereas an electric bulb can be connected with a two-pin plug?
She wrote: Three-pin connections reduce heating of connecting wires.
- Is her answer correct or incorrect? Justify.
- What is the function of a fuse in a domestic circuit?
An electric iron of resistance 20 Ω draws a current of 5 A. The heat developed in the iron in 30 seconds is ______.
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?
