Question

If a piece of metal was thought to be a magnet, which one of the following observations would offer conclusive evidence
A) It attracts a known magnet
B) It repels a known magnet
C) Neither (a) nor (b)
D) It attracts a steel screw driver

Answer 1

Hint:
Magnet is a substance which produces magnetic fields and attracts the same poles as well as repelling opposite poles. Attraction between two substances does not give us proper evidence whether they are magnetic or not. As one magnet and iron metal also attract each other.




Complete step by step solution:

It is also a hit and trial method question. Here we have to judge the option one by one logically. So, let’s start. But before starting let’s know some points about the magnet.
Magnets are objects that produce a magnetic force. This force can cause metal objects to move or stick to them. Magnets have two poles,named as north pole and south pole. The north pole of a magnet will attract the south pole of another magnet, and the south pole of a magnet will attract the north pole of another magnet.

 Now move into the question. First option is to attract a known magnet. Yes, it is true that it can attract a known magnet when opposite poles of them are facing each other. But think that metal is not a magnet then it is attracted by the known magnet because magnets attract all magnetic metrical. So, by only knowing this statement we can’t conclude that if the metal attracts a known magnet, then it is a magnet.

Now move to the next option. We know that when the same poles of two magnets are facing each other then they will repel and we can only say that a magnet can attract a magnetic material like metal. So, by this we can conclude that if the metal and known magnet repel each other then the metal is also a magnet.
Hence our correct option is (B).





Note:
Magnets have two poles which are named north pole and south pole. The north pole of a magnet will attract the south pole of another magnet, and the south pole of a magnet will attract the north pole of another magnet. same poles of two magnets facing repulsion to each other.