Question

The values of current I flowing in a given resistor for the corresponding values of potential difference V across the resistor are given below: I (ampere) 0.5 1.0 2.0 3.0 4.0 V (volt) 1.6 3.4 6.7 10.2 13.2
Plot a graph between V an I and calculate the resistance of the resistor.

Answer 1

V - I graph as shown in figure . Here points lie on the equation of line {where variables are V and I } are (1.6 ,0.5) , (3.4,1.0) , (6.7, 2.0) , (10.2, 3.0) and (13.2, 4.0)

Now , use Ohm's law ,
V = IR
R = V/I , means Resistance is the slope of graph V - I
So, R = (V₂ - V₁)/(I₂ - I₁)
V₂ = 3.4V, V₁ = 1.6V , I₂ = 1A and I₁ = 0.5A
So, R = (3.4 - 1.6)/(1 - 0.5) = 1.8/0.5 = 3.6

Hence, resistance , R = 3.6Ω
similarly R= (V₃ - V₂)/(I₃ - I₂) = (6.7 - 3.4)/(2 - 1) = 3.3
R = (V₄ - V₃)/(I₄ - I₃) = (10.2 -6.7)/(3-2) = 3.5
R=(V₅ - V₄)/(I₅ - I₄) = (13.2 - 10.2)/(4-3) = 3
here R is variable so, take average of all . Rav = (3.6 + 3.3 + 3.5 + 3)/4 = 13.4/4 = 3.35Ω
hence, resistance = 3.35Ω

Answer 2

Answer: Resistance will be 3.3 ohm