Advertisements
Advertisements
प्रश्न
A coil of insulated copper wire is wound around a piece of soft iron and current is passed in the coil from a battery. What name is given to the device so obtained? Give one use of the device mentioned by you.
Advertisements
उत्तर
The device formed is an electromagnet.
Use:
For separating the magnetic substances such as iron from other debris.
APPEARS IN
संबंधित प्रश्न
The incomplete diagram of an electric bell is given in Figure. Draw winding of coil on the core and complete the electric circuit in the diagram.
G-Gong, H-Hammer, A-Armature, C-Core, B-Battery.
Name one device that uses an electromagnet.
The strength of the electromagnet can be increased by
The following figure shows a coil wound around a soft iron bar XY.
- State the polarity at the ends X and Y as the switch is pressed.
- Suggest one way of increasing the strength of electromagnet so formed.
State two differences between an electromagnet and a permanent magnet.
How is the working of an electric bell affected, if alternating current be used instead of direct current?
Name the material used for making the armature of an electric bell. Give a reason for your answer.
Explain, why steel is used in preference to soft iron for making permanent magnets while soft iron is used in preference to steel for making electromagnets.
What is an electroscope? Describe the different stages of charging a gold leaf electroscope negatively with the help of a diagram.
Explain the working of the following device.
Speaker
