Question

Which of the following doesn’t use electromagnet?
(A) Electric bell
(B) Electric fan
(C) Magnetic stickers
(D) Televisions

Answer 1

Hint: It is important to know why certain devices have an absolute need for a working electromagnet for their proper functioning, whereas some devices have no need for electromagnets. We have to remember that a wide range of devices have need for electromagnets as electromagnets have the ability to increase or decrease the value of the current.

Complete step by step answer:
Any type of electrical appliance which has a requirement for changing currents require a working electromagnet for their proper functioning.
An electric bell requires a working electromagnet as when the switch of the electric bell is pressed the current starts flowing in the electromagnet which attracts a metal hammer. The hammer hits the bell and produces a ringing sound. An electric bell would not be able to function without a working electromagnet. Thus option (A) is incorrect.
Similarly electric fans and televisions also require changing values of currents for their proper working. Thus, electric fans and televisions have electromagnets and coils inside them which help in changing the value of currents inside these devices. Thus options (B) and (D) are also incorrect.
Magnetic stickers on the other hand have no requirements for changing currents and hence do not require an electromagnet for their basic functions. Magnetic stickers are attached with weak magnetic strips which allow them to stick to metallic surfaces of refrigerators and wardrobes.
Thus option (C) is the correct answer.

Note: It is important to know that electromagnets have various different uses. Electric bells use the induced magnetic property of electromagnets whereas electric fans and televisions use the changing currents property of electromagnets.