Experimentally prove that in series combination of three resistances: (a) Current flowing through each resistance is same , and (b) total potential difference is equal to the sum of potential differences across individual resistors.

Experimentally prove that in series combination of three resistances:

1.	Experimentally prove that in series combination of three resistances: (a) Current flowing through each resistance is same , and (b) total potential difference is equal to the sum of potential differences across individual resistors.
Answer» Solution :Series combination of resistors: We take THREE resistors `R_1,R_2 and R_3` and JOIN them in series between the points X and Y in an electric circuit as shown in fig.12.51. (a) Plugthe key and note the ammeter reading. Then CHANGE the position of ammeter to anywhere in between the resistors and again note the ammeter readings. We find that ammeter reading remains unchanged. It shows that in series ARRANGEMENT same current flows through each resistor. (b) Insert a voltmeter across the ends X and Y of the series combination of resistors. Plug the key so as to complete the circuit and note the voltmeter reading V across the series combination of resistors. Take out plug from key K and disconnect the voltmeter. Now insert the voltmeter across the ends of first resistor `R_1` as shown in Fig.12.52. Plug the key and note the voltmeter reading `V_1`. Similarly, measure the potential difference across the other two resistors `R_2 and R_3` separately. Let these potential difference be `V_2 and V_3` respectively. Experimentally we find that `V=V_1+V_2+V_3` It shows that in series arrangement of resistors total potential difference is equal to the sum of potential differences across individual resistors.