Electric Current and its Effects — Science STD 7 — Question
Gujarat BoardEnglish MediumSTD 7ScienceElectric Current and its Effects1 Mark
MCQ
Name one device that uses an electromagnet.
✓
Electric bell
B
Barometer
C
Lactometer
D
All the above
✓
Answer
Correct option: A.
Electric bell
An electromagnet is a type of magnet in which the magnetic field is produced by an electric current.
The magnetic field disappears when the current is turned off.
Electromagnets usually consist of a large number of closely spaced turns of wire that create the magnetic field.
The wire turns are often wound around a magnetic core made of generally iron.
Electromagnets are widely used as components of electrical devices such as Electric Bell ,motors, generators, loudspeakers, hard disks, $\ce{MRI}$ machines, scientific instruments, etc.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.