Question

100 J of work is done in transferring 20 C of charge between two points in a conductor. Find the
resistance offered by the conductor if a current of 2 A flows through it​

Answer 1

Given :

➳ Work done moving a charge b/w two points in a conductor = 100J

➳ Magnitude of charge = 20C

➳ Current flow = 2A

To Find :

⟶ Resistance of conductor.

SoluTion :

➨ Work done in moving a charge b/w two points is given by

• W = q × ΔV

➨ As per ohm's law, Current flow in a conductor is directly proportional to the applied potential difference.

• V = IR

✴ Potential diffrence b/w two points :

⇒ W = q × ΔV

⇒ ΔV = W/q

⇒ ΔV = 100/20

⇒ ΔV = 5 volt

✴ Resistance of conductor :

➾ V = I × R

➾ R = V/I

➾ R = 5/2

➾ R = 2.5Ω

Answer 2

Given ,

Work done (W) = 100 J

Charge (q) = 20 C

Current (I) = 2 A

We know that ,

The work done to move a unit charge from one point to another point is called potential difference

V = W/q

Thus ,

V = 100/20

V = 5 volt

Now ,

V = IR { By ohm's law }

Thus ,

5 = 2 × R

R = 5/2

R = 2.5 ohm

$\sf \therefore \underline{ { The \: resistance \: offered \: by \: the \: conductor \: is \: 2.5 \: ohm}}$