Question

The current-voltage graph for a given metallic wire at two different temperatures $ {{T}_{1}} $ and $ {{T}_{2}} $ is shown in the figure. The temperatures $ {{T}_{1}} $ and $ {{T}_{2}} $ are related as

• A. $ {{T}_{1}}>{{T}_{2}} $
• B. $ {{T}_{1}}<{{T}_{2}} $
• C. $ {{T}_{1}}={{T}_{2}} $
• D. $ {{T}_{1}}>2{{T}_{2}} $

Answer 1

Answer: (B)

Slope of the V-i curve at any point is equal to resistance at that point. From the curve slope for $ {{T}_{1}}> $ slope for $ {{T}_{2}} $ $ {{R}_{{{T}_{1}}}}<{{R}_{{{T}_{2}}}} $ $ \Rightarrow $ Also at higher temperature resistance will be higher so $ {{T}_{2}}>{{T}_{1}}. $