JEE Main 2021 · PhysicsNumerical answerNumerical valueEasyCalculation

JEE Main 18 March 2021, Shift 2, Physics Q23

Question 23 of 90 in this shift, Physics question 23 of 30, Section B.

Two wires of same length and thickness having specific resistances 6

\Omega

cm and 3

\Omega

cm respectively are connected in parallel. The effective resistivity is

\rho

\Omega

cm. The value of

\rho

, to the nearest integer, is _________.

Official answer

NTA final key.

Chapter: Current Electricity
Topic: Ohm's Law and Resistance
Idea tested: Resistivity and Geometry

Same idea in other shifts

Asked 10× in all

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22 Jul 2021, Shift 2 · Q7A 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…EasySingle correctHas a figure

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.