Question

The values of current I flowing in a given resistor for the corresponding values of potential difference V applied across the ends of resistor are given below in the table:

I (Amperes)	0.4	0.8	1.2	1.6	2.0
V (Volts)	1.2	2.4	3.6	4.8	6.0

Plot a graph between V and I and calculate the resistance of that resistor.

Answer 1

V = 1.2 V    ...[2.4 V − 1.2 V)

I = 0.4 A    ...[0.8 A − 0.4 A]

∴ Resistance (R) = `V/I`

= `1.2/0.4`

= 3 Ω

The accuracy of the graph’s plotting determines the value of R that is found on it.