Correct answer: 1 volt
Explanation:
By definition, electric potential (voltage) is the work done per unit charge to move a charge between two points. Mathematically, \[ \text{Voltage (V)} = \frac{\text{Work (Joule)}}{\text{Charge (Coulomb)}} \] So, \[ 1 \ \text{volt} = \frac{1 \ \text{joule}}{1 \ \text{coulomb}} \]
Hence, the correct answer is: 1 volt.

The equivalent resistance between the points \(A\) and \(B\) in the given circuit is \[ \frac{x}{5}\,\Omega. \] Find the value of \(x\). 
A Wheatstone bridge is initially at room temperature and all arms of the bridge have same value of resistances \[ (R_1=R_2=R_3=R_4). \] When \(R_3\) resistance is heated, its resistance value increases by \(10%\). The potential difference \((V_a-V_b)\) after \(R_3\) is heated is _______ V. 