Physics
Grade-7
Easy
Question
Tungsten is used for the manufacture of an electric bulb because
- It is inexpensive
- It is malleable
- It is a good conductor
- It has a very high melting point
Hint:
It has a very high melting point
The correct answer is: It has a very high melting point
Tungsten is used in due to high melting point and resistivity and does not oxidize. Thus, the filament of tungsten does not melt even though a large amount of heat is generated due to the passage of the current to through the filament.
Related Questions to study
Physics
Which of the following does NOT contain a heating element?
- Electric oven
- Electric bell
- Electric heater
- Electric iron
Which of the following does NOT contain a heating element?
PhysicsGrade-7
- Electric oven
- Electric bell
- Electric heater
- Electric iron
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What are the factors upon which the amount of heat produced in a wire depends?
(i) Material
(ii) Length
(iii) Thickness
- Only (i) and (ii)
- (i), (ii) and (iii)
- Only (ii) and (iii)
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What are the factors upon which the amount of heat produced in a wire depends?
(i) Material
(ii) Length
(iii) Thickness
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- Only (i) and (ii)
- (i), (ii) and (iii)
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- Only (i) and (iii)
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Select the one in which the heating effect of current is not used.
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Select the one in which the heating effect of current is not used.
PhysicsGrade-7
- Electric geyser
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- A battery
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Identify the element that is used for making the filament in bulbs.
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Identify the element that is used for making the filament in bulbs.
PhysicsGrade-7
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A fuse is fixed in a circuit to
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- Increase the power consumed in the circuit
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A fuse is fixed in a circuit to
PhysicsGrade-7
- Increase the amount of current
- Increase the power consumed in the circuit
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- Decrease the amount of current
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Which of the following effects of electric current is made use of in the figure shown below?

- Heating
- Magnetic
- Chemical
- All of these
Which of the following effects of electric current is made use of in the figure shown below?

PhysicsGrade-7
- Heating
- Magnetic
- Chemical
- All of these
Physics
The wire used in a fuse has
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- Low melting point
- High melting point
- All of these
The wire used in a fuse has
PhysicsGrade-7
- Average melting point
- Low melting point
- High melting point
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A device that breaks the electric circuit in the case of excess current is called
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- Earth wire
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- Voltmeter
A device that breaks the electric circuit in the case of excess current is called
PhysicsGrade-7
- Switch
- Earth wire
- Fuse wire
- Voltmeter
Physics
Choose the correct statement about an electric fuse.
- Fuses are an important part of all electrical appliances.
- A maximum limit on the flow of an electric current in an electric circuit is fixed.
- A minimum limit on the flow of an electric current in an electric circuit is fixed.
- A fuse blows off if the current exceeds the safe limit.
Choose the correct statement about an electric fuse.
PhysicsGrade-7
- Fuses are an important part of all electrical appliances.
- A maximum limit on the flow of an electric current in an electric circuit is fixed.
- A minimum limit on the flow of an electric current in an electric circuit is fixed.
- A fuse blows off if the current exceeds the safe limit.
Physics
DIRECTIONS: Read the following two statements carefully and choose the correct options.
Statement 1: The heating up of a thin conducting wire on passing an electric current through it is called the heating effect of current.
Statement 2: Various electrical appliances that are based on the heating effect of current contain a coil of wire called an element.
- Statement (2) is correct, while statement (1) is incorrect.
- Both statements are correct.
- Statement (1) is correct, while Statement (2) is incorrect.
- Both statements are incorrect.
DIRECTIONS: Read the following two statements carefully and choose the correct options.
Statement 1: The heating up of a thin conducting wire on passing an electric current through it is called the heating effect of current.
Statement 2: Various electrical appliances that are based on the heating effect of current contain a coil of wire called an element.
PhysicsGrade-7
- Statement (2) is correct, while statement (1) is incorrect.
- Both statements are correct.
- Statement (1) is correct, while Statement (2) is incorrect.
- Both statements are incorrect.
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In which one of the following conditions the amount of heat produced in a current-carrying wire will increase?
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- When the amount of current passing in the wire is decreased
- All of these
In which one of the following conditions the amount of heat produced in a current-carrying wire will increase?
PhysicsGrade-7
- When terminals of are changed
- When the amount of current passing in the wire is increased
- When the amount of current passing in the wire is decreased
- All of these
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When current is passed through a conductor, the heat produced in it depends upon
I. The material of the conductor
II. The current flowing through the conductor
III. The time for which the current flows
- I and II only
- I and III only
- II and III only
- All I, II, and III
When current is passed through a conductor, the heat produced in it depends upon
I. The material of the conductor
II. The current flowing through the conductor
III. The time for which the current flows
PhysicsGrade-7
- I and II only
- I and III only
- II and III only
- All I, II, and III
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Which has no importance for fuse wire?
- Current passing through the wire
- Specific resistance of the wire
- Length of wire
- Diameter of wire
Which has no importance for fuse wire?
PhysicsGrade-7
- Current passing through the wire
- Specific resistance of the wire
- Length of wire
- Diameter of wire
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The given images show a

- Battery
- Cell
- Switch
- Plug
The given images show a

PhysicsGrade-7
- Battery
- Cell
- Switch
- Plug
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In which of the following circuits bulb will glow?
In which of the following circuits bulb will glow?
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