Wat is d drawback of ohms law?

Your first answer is partically correct but to add to that... V=iR for steady state conditions. AC circuits are never steady state, the direction of current flow changes from forward to backward 60 times a second. V=iR does not apply to transient conditions when DC current is intially turned on or off. V=iR does not apply to LC circuits (inductive or capacitive circuits). But, other than the exceptions, Mr Ohm came up with a very powerful observation.