A student obtained a graph while conducting an experiment to study the dependence of current (𝐼) on the potential difference (𝑉) across a resistor, 

(i) What is the relation between the current and the potential difference from the graph? 

(ii) When the potential difference across it is 2. 5𝑉 what is the current that flows through the resistor?

(i) As the graph depicts, the resistance (slope) is constantly increasing, which explains that the potential difference and the current are proportionately increasing. 

So, 𝐼 ∝ 𝑉 (Based on Ohm's law)

(ii) According to Ohm's law,

R = V/I

$\Rightarrow \mathrm{R}=\frac{1}{0.1}$

⇒ 𝑅 = 10 Ω

Again, taking ohm's law,

R = V/I

⇒ I = V/R

⇒ I = 2.5/10 = 0.25 A

Hence, 0. 25 𝐴 current flows through the resistor when the potential difference across it is 2. 5 𝑉.