JEE Main 2018PhysicsCurrent ElectricityHardMCQ

JEE Main 2018 — Current Electricity Question with Solution

JEE Main 2018 (08 Apr)

Question

On interchanging the resistances, the balance point of a meter bridge shifts to the left by 10 cm. The resistance of their series combination is 1 kΩ . How much was the resistance on the left slot before interchanging the resistances?

Choose an option

Show full solutionCorrect option: D
Correct answer
D550 Ω

Step-by-step explanation


ab=l100-l     

a+b=1000

b a = l−10 110−l

100−l l = l−10 110−l

l 2 −10l=11000+ l 2

−100 l=110 l

200l=11000

l= 110 2 =55

55 45 = a b

⇒a=550 Ω     b=450 Ω

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About this question

This is a previous-year question from JEE Main 2018, covering the Current Electricity chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.