State Ohm's Law and how to verify it
Statement: At constant temperature, the current (I) through a conductor is directly proportional to the potential difference (V) across its ends.
V ∝ I → V = IR
Verification:
Connect resistor in series with battery, rheostat, and ammeter. Connect voltmeter across resistor.
Vary the rheostat; note V and I at each setting.
Calculate V/I each time if it's constant, Ohm's Law is verified.
Plot V vs I → a straight line through origin confirms it. Slope = R.