Four resistors, each of resistance $ R $, are connected as shown in the figure below. 
In this circuit, the resistors are connected in a combination of series and parallel.
Let's break it down:
- Resistors between points 1 and 6 are in series, so the total resistance between points 1 and 6 will be the sum of the resistances of the two resistors connected in series: \[ R_{\text{total between 1 and 6}} = R + R = 2R \]
- Resistors between points 3 and 6 are in parallel. The equivalent resistance \( R_{\text{eq}} \) for two resistors \( R \) in parallel is given by: \[ R_{\text{eq}} = \frac{R \times R}{R + R} = \frac{R}{2} \] - The total resistance between points 2 and 4 is the parallel combination of two resistors each of resistance \( R \): \[ R_{\text{total between 2 and 4}} = \frac{R}{2} \]
Thus, the total resistance between points 2 and 4 is \( 0.5R \).
Assertion (A): We cannot form a p-n junction diode by taking a slab of a p-type semiconductor and physically joining it to another slab of an n-type semiconductor.
Reason (R): In a p-type semiconductor, \( n_e \gg n_h \) while in an n-type semiconductor \( n_h \gg n_e \).
The graph shows the variation of current with voltage for a p-n junction diode. Estimate the dynamic resistance of the diode at \( V = -0.6 \) V.
