Physics
The strength of an electromagnet can be increased by:
- reversing the directions of current
- using alternating current of high frequency
- increasing the current in the coil
- decreasing the number of turns of coil
Related Questions
You are required to make an electromagnet from a soft iron bar by using a cell, an insulated coil of copper wire and a switch. (a) Draw a circuit diagram to represent the process. (b) Label the poles of the electromagnet.
State two differences between an electromagnet and a permanent magnet.
Show with the aid of a diagram how a wire is wound on a U-shaped piece of soft iron in order to make it an electromagnet. Complete the circuit diagram and label the poles of the electromagnet.
Describe the construction and working of an electric bell with the help of a neat and labelled diagram.