What is series combination of resistances? You have been given three resistances R 1 , R 2 , R 3 Ω . Connect them in series combination. Draw its electric circuit and write the value of equivalent resistance.

The resistors are connected one next to another is called series combination of resistors. Consider the three resistors R 1 , R 2 and R 3 are connected in series with battery, ammeter and voltmeters as shown in the circuit diagram. Let I be the current and V 1 , V 2 and V 3 are the potential differences across resistors R 1 , R 2 and R 3 respectively. The total potential difference across a combination of resistors in series is equal to the sum of potential differences across the individual resistors. V = V 1 + V 2 + V 3 According to ohm's law V = I R s (Where R s is the equivalent resistance of the series circuit) V 1 = I R 1 , V 2 = I R 2 and V 3 = I R 3 I R s = I R 1 + I R 2 + I R 3 R s = R 1 + R 2 + R 3 Hence the proof.

Establish relation between potential difference V and electric current I by plotting graph.

According to Ohm's law. V ∝ I V I = R constant (where R is resistance) Following circuit diagram is used to verify the Ohm's law. Plotting a graph between V and I is shown in the following diagram. The slope of a V - I graph represents the resistance.

The potential difference V , across the ends of a given metallic wire in an electric circuit is directly proportional to the current I flowing through it, provided its temperature remains the same. This is called Ohm's law. V ∝ I V I = R constant (where R is resistance) Following circuit diagram is used to verify the Ohm's law.