Non- Reversible changes= Changes which cannot be reversed are called non- reversible changes. It is also called chemical changes. For example Burning of thread.
Reversible changes= Changes which can be reversed are called reversible changes. It is also called physical changes. For example melting of ice.
IN THIS PROCESS , FIBERS FROM A MASS OF COTTON WOOL ARE DRAWN OUT AND TWISTED THIS BRINGS THE FIBER TOGETHER TO FORM A YARN.
The process is called spinning.