It should be remembered that while Ohm’s law seems to be very effective, it still has some limitations that should be noted. For example, it will not show details about how semiconductor devices will behave. Another thing is that it cannot be 100% accurate especially when some properties of the item that is being measured changes.
Non-linear elements cannot be measured and used with Ohm’s law too. This is something that you should take note before you decide if this is something that you should use for measuring or not. One example of an item that cannot be measured with Ohm’s law is the filament lamp.
One reason Ohm’s law fails is because temperature, especially in some devices, will rise as the current is increased. So, Ohm’s law doesn’t fail in all real life calculations.
For example, in a filament light bulb the temperature will rise as the current is increased so Ohms’ law will result in an inaccurate result. If the temperature could be kept constant by using smaller currents, then Ohm’s law would produce an accurate result.