An electromagnet is used to remove a splinter from an eye. What material is the splinter made of?
A) Aluminium
B) Glass
C) Iron
D) Wood

Hint: As we know that an electromagnet is a substance that uses current. It can be switched on or switched off. The coils used for electromagnet are generally made up of copper wire because copper is a good conductor of electricity.

Complete step by step solution:
As we all know that an electromagnet is a softcore magnet which is made by passing through an electric current within a coil.
Now, a Splinter is a thin piece of material like wood, glass, or metal which gets inserted below the top layer of the skin.
As given in that an electromagnet is used to get the splinter out of the eye. Therefore, the material used in the splinter is iron.

Therefore, option (C) is the correct option.

Additional Information:
Now, let us know more applications of an electromagnet.
IN AN ELECTRIC BELL: the electromagnets are used in the electric bells as electromagnets help the hammer to vibrate back and forth that enables the bell to ring.
IN AN ELECTRIC LOCK: you might have seen that when someone answers the entry phone, the door is unlocked from the upstairs flat. It is because the electromagnet used pulls the bolt in the door.
IN CRANES: the electromagnet used in the cranes enables them to lift tons of steel without hooks and rope.
MICROSURGERY: Researchers are working on making a micro-robot with the use of an electromagnet that can move into the body for taking out surgery without cutting the body open.

Note: As we know, the copper wire carrying a current has a magnetic field like a bar magnet, but we can switch it on and off and can reverse them. In an application like MRI scanning the current in the coil is reversed millions of times per second. We can also increase the magnetism power of an electromagnet by increasing the number of turns of the coil and by increasing the current flowing in the coil.