What are the equipments used in ohm law?

Your question in ambiguous. Are you asking what equipment you need to provewhether or not Ohm's Law applies to a particular load? If so, then you need a variable voltage supply, a voltmeter, and an ammeter. As you gradually increase the voltage across the load, you will need to record the voltage and current values. If the resulting graph is a straight line, then the load is 'ohmic' (or 'linear') and obeys Ohm's Law. If the resulting graph is a curved line, then the load is 'non-ohmic' (or 'non-linear') and does not obey Ohm's Law.