Advertisements
Advertisements
प्रश्न
How does the wire in the filament of a light bulb behave differently to the other wires in the circuit when the current flows?
What property of the filament wire accounts for this difference?
Advertisements
उत्तर
| Filament of a light bulb | Connecting wire |
| The wire in the filament of a light bulb has a high resistance and a high melting point. So, it heats up without melting and glows when the current flows through it. | The connecting wire in a circuit has a low resistance and a low melting point. So, it does not heat up much when the current flows through it and thus does not glow. |
It is the high melting point of the filament wire that is accountable for this difference.
APPEARS IN
संबंधित प्रश्न
Why does the cord of an electric heater not glow while the heating element does?
An electric heater of resistance 8 Ω draws 15 A from the service mains 2 hours. Calculate the rate at which heat is developed in the heater.
When current is switched ‘on’ in a room heater, it ______.
Solve the following example.
Two tungsten bulbs of wattage 100 W and 60 W power work on 220 V potential difference. If they are connected in parallel, how much current will flow in the main conductor?
Why does tungsten metal used to make solenoid type coil in an electric bulb?
The ‘live’ and the ‘neutral’ wires have potential difference of _______.
In an electric bulb, coil of _______ metal is used.
These days when current in the circuit suddenly increases _______ switches are used.
Find the odd one out and give its explanation.
Which metal is used to make the filament of an electric bulb?
An electric bulb is connected to a 220 V generator. The current is 0.50 A. What is the power of the bulb?
Which of the following gases are filled in electric bulbs?
How does use of a fuse wire protect electrical appliances?
When a switch is in OFF position,
- circuit starting from the positive terminal of the cell stops at the switch.
- circuit is open.
- no current flows through it.
- current flows after some time.
Choose the combination of correct answer from the following.
What is an electric fuse made up of?
Explain the working of an electric fuse.
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.
Fuse is a strip of alloy wire which is made up of lead and tin with a very low ______.
Explain why fuse wire is always connected in a series arrangement.
When a current I flows through a wire of resistance R for time t then the electrical energy produced is given by ______.
