Because that was the standard decided upon in Great Britain. When electricity was introduced to India the engineers were British and followed that convention.
220V , 50Hz
Yes, using a 220v-60hz microwave in Australia is fine. The voltage of alternating current supplied to homes in Australia is 220v. The frequency of the voltage is 50hz.
you can't
Yes, no problem.
220v 50Hz
nothing
There should be no problem at all.
220V 50Hz
Yes no problem the transformer should run a little cooler as well.
It is possible that the waffle maker will operate on a 220v 50hz power supply, but there is a risk that it may not function optimally or may overheat. It is recommended to check the manufacturer's specifications or contact them directly to confirm compatibility.
More than likely yes it will work just fine.
The information given in the answer to the Related Question shown below may be relevant.