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Question
A student carries out an experiment and plots the V-I graph of three samples of nichrome wire with resistances R1, R2 and R3 respectively. Which of the following is true?
Options
R1 = R2 = R3
R1 > R2 > R3
R3 > R2 > R1
R2 > R3 > R1
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Solution
R3 > R2 > R1
Explanation -
Since the current (I) is plotted on y-axis and potential difference (V) is plotted on x-axis, so the slope of the graph is `1/"R"`. It means higher the slope, the lesser is the resistance. So, R1 will be minimum and R3 will be maximum.
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