COMEDK20269 May 2026Evening ShiftPhysicsCurrent ElectricityActual
The voltage – current graph for a metal wire of uniform area of cross section at two different temp T and T' is shown. Then choose the correct statement:
Options
- ATemperature T' is greater than temperature T
- BResistance of the conductor at temperature T is greater than resistance of the conductor at temperature T'
- CResistivity is independent of temperature
- DTemperature T is greater than temperature T'
Correct answer
A. Temperature T' is greater than temperature T
Step-by-step solution
From Ohm's law, V = IR , which gives R = V I . The given graph is an I-V plot. The slope of this graph is I V = 1 R . From the graph, for a given voltage V , the current I at temperature T is greater than the current I' at temperature T' ( I > I' ). Therefore, the slope of the line for T is greater than the slope of the line for T' . This implies 1 R_T > 1 R_ T' , which means R_T For a metal wire, resistance increases with an increase in temperature. Since the resistance at T' is greater than the resistance at T ,