Physics · 2021
JEE Main · 22 July 2021, Shift 2 · Q7
A Copper (Cu) rod of length 25 cm and cross-sectional area 3 mm^2 is joined with a similar Aluminium (Al) rod as shown in figure. Find the resistance…
A Copper (Cu) rod of length $\displaystyle 25$ cm and cross-sectional area $\displaystyle 3 \mathrm{~mm}^2$ is joined with a similar Aluminium (Al) rod as shown in figure. Find the resistance of the combination between the ends A and B.
(Take Resistivity of Copper $\displaystyle =1.7 \times 10^{-8} \Omega \mathrm{~m}$
Resistivity of Aluminium $\displaystyle =2.6 \times 10^{-8} \Omega \mathrm{~m}$ )
Official answer
(2)
$\displaystyle 0.858 \mathrm{~m} \Omega$
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.