The graphs between current (I) and voltage (V) for three linear resistors 1,2 and 3 are given below : If Ri, R2 and R3 are the resistances of these resistors, then which one of the following is correct?

According to Ohm's Law, the relationship between voltage (V) and current (I) is linear, where V = IR. In a graph where current (I) is plotted on the y-axis and voltage (V) on the x-axis, the slope of the line represents the conductance (I/V), which is the reciprocal of resistance (1/R) [1]. Consequently, a steeper slope indicates a higher conductance and a lower resistance. Conversely, if the graph plots V on the y-axis and I on the x-axis, the slope directly represents the resistance (R). In standard I-V characteristic representations for resistors 1, 2, and 3, the line closest to the voltage axis (lowest slope in an I vs V plot) corresponds to the highest resistance. Based on the typical visual arrangement of such problems where resistor 3 has the lowest slope relative to the voltage axis, the resistance order is R3 > R2 > R1.

Sources

1. [1] Science , class X (NCERT 2025 ed.) > Chapter 11: Electricity > Figure 11.3 > p. 176