The increase in length due to the weight of the wire can be calculated using the formula for elongation under tension:
\( \Delta L = \frac{F L}{A Y} \), where \( F = \rho g L^2 \) is the force due to the weight, and \( Y \) is the Young's modulus.
The circuit shown in the figure contains two ideal diodes \( D_1 \) and \( D_2 \). If a cell of emf 3V and negligible internal resistance is connected as shown, then the current through \( 70 \, \Omega \) resistance (in amperes) is: 