JEE Main 2022 · PhysicsNumerical answerNumerical valueEasyCalculation

JEE Main 25 July 2022, Shift 1, Physics Q58

Question 58 of 90 in this shift, Physics question 28 of 30, Section B.

Eight copper wire of length

l

and diameter

d

are joined in parallel to form a single composite conductor of resistance

R

. If a single copper wire of length

2l

have the same resistance (

R

) then its diameter will be ______

d

Official answer

NTA final key (2022 Session 2).

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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29 Jul 2022, Shift 1 · Q42Two metallic wires of identical dimensions are connected in series. If $\sigma_1$ and $\sigma_2$ are the conductivities of the these wires…MediumSingle correct
30 Jun 2022, Shift 1 · Q45An electric cable of copper has just one wire of radius 9 mm. Its resistance is 14 $\Omega$ . If this single copper wire of the cable is…EasySingle correct
4 Aug 2021, Shift 1 · Q21A wire of length L is coated by another conducting material of double resistivity and the thickness of the layer is equal to the radius of…MediumNumerical valueHas a figure
26 Aug 2021, Shift 1 · Q17What equal length of an iron wire and a copper-nickel alloy wire, each of 2 mm diameter connected parallel to give an equivalent…MediumSingle correct
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
18 Mar 2021, Shift 2 · Q23Two wires of same length and thickness having specific resistances 6 $\Omega$ cm and 3 $\Omega$ cm respectively are connected in parallel.…EasyNumerical value

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.