Name two devices in which electromagnets are used and also name two devices where permanent magnets are used:
Hint: In nature, there are many magnets found which exhibit magnetic properties naturally such magnets are called natural magnets such as magnetite. But some are man-made or synthetic magnets such as electromagnets and some permanent magnets.
Complete answer: Let us first know the basic meaning of electromagnet and permanent magnets. An electromagnet is a magnet which is made using a soft piece of metal in which an electrical wire wrapping is done and then electrical current is passed through it, as soon as current is passed through the device it behaves as magnet and is called electromagnet.
Electric bell and Electric motors are two common examples of devices in which electromagnets are used. In electric motors as soon as current is passed the magnetic field exerts a force which in turn produces a rotation of the connected motor.
Some of the materials are in nature which produce a magnetic field due to its nature of formation of molecules and this magnetic field depends upon the inner structure of the material. Refrigerator doors and toys are the two most common examples of devices in which permanent magnets are used.
Note: It should be remembered that an electromagnet can be used in a wide purpose of electromagnetism areas such as hard disks, speakers and many scientific instruments. And permanent magnets can also be used in televisions, phones, generators and in many other appliances.