Question

A device of resistance r is connected acrosss a source of v and draws a currrent i. devine an expression

Answer 1

HELLO THERE!

Your question is an indirect one, which actually says to "derive Ohm's Law".

Given: Current i is drawn by a resistor of resistance r, from a current source of Potential difference v.

Now, we know that as you increase the Potential difference (v), the current in the circuit increases.

So, i is directly proportional to v.

Or, v = k. i

(where k is a constant of proportionality).

k = r (the resistance of the device).

So, v = ir.

This was the required expression relating v, i and r.

HOPE MY ANSWER IS SATISFACTORY...

Thanks!