Basis for Comparison | Electromagnet | Permanent Magnet |
---|---|---|
Generation of the magnetic field | Due to electric current | Due to material characteristics when magnetized. |
Strength of magnetic field | The strength of the field depends on the total current flowing through the solenoid or coil. | Here the magnetic field strength solely relies on the respective material. |
Magnetization | Temporary | Permanent |
Type of material used | Generally the soft iron core | Usually, it makes use of hard material. |
Demagnetization | It is demagnetized when the flow of current is stopped. | The material is demagnetized when it is subjected to extremely high temperatures. |
The requirement of external power | Exist | Not Exist |
Magnetic field retention | The field is retained till the time current flows through the material | These materials retain the field all the time. |
Cost | Low | Comparatively high |
Poles of the magnet | Can be varied. | Here the poles can never be changed. |
Example | A solenoid across an iron | Bar Magnet |
Applications | Electric bells, loudspeakers, motors, etc. | Cell phones, headphones, sensors, etc. |
No comments:
Post a Comment