Permanent magnetic speakers are perfect examples of electromagnetic devices. The operation of these devices is based on the principle of electromagnetism. A metal coil is attached to a permanent magnet and when current passes through the coil it generates a magnetic Weld which is amplified by the cone like structure and gives a sound.
1. Which two devices are electromagnetic devices?
a. Pen,Television
b. Radio,Bulb
c. Television,radio
d. Pen,Bulb
2. What will happen if you detach the permanent magnet from the metal coil?
a. Speakers won't work
b. Sound will get more amplified
c. No change to the sound
d. Both B and C
3. Which part of the speaker amplifies the sound?
a. Metal coil
b. Magnet
c. cone-like structure
d. All of the above
4. When is magnetic field generated in the speaker?
a. When you speak loudly into it
b. When you hold it
c. When you hear its voice
d. When you pass current through it
5. Identify a device which works with electromagnets.
a. Generators
b. Stapler
c. Gas stove
d. Air conditioner
