How is the single-touch method of magnetism different from the double touch method ?
Hint:Methods of making artificial magnets by rubbing a permanent magnet over it,in the same direction or by using two magnets instead of one. Magnetism is the force which is exerted by magnets on each other when they attract or repel each other.
Complete answer: Motion of electric charges causes magnetism. Here we will discuss the single and double method of magnetism. In the single-touch method the magnet is rubbed over the bar (iron bar) in the same direction. For the single-touch method one end of the magnet (let north pole) is placed at one end (let X) of the iron bar and then rubbed over the iron bar from one end to other end (let Y), then lifted and brought back to the end $X$. This process is repeated a few times. It is observed that the original end that is end $X$ will become North pole and end $Y$ becomes South pole.
In a double- touch method of magnetising an iron bar by simultaneously stroking it with two opposite poles of two bar magnets. For the double-touch method take an iron bar, let say $AB$ and place it over the two magnets as shown in the diagram. Now take another two magnets and start rubbing them in the opposite direction away from each other.
This is the complete explanation of the single and double touch method and how differently they both are done.
Note: In double-touch method never slide both the magnets in the same direction.Both the magnets are to be slid in two different directions. Other changes can be seen in the single touch method so read the question properly.