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QJEEM20Ph7ebf: JEE Main 2020 Physics - Class 12 JEEM20Ph7ebf Solution: Two isolated conducting spheres S 1 and S 2 of radius and have…

Two isolated conducting spheres S1 and S2 of radius 23R{2 \over 3}R and 13R{1 \over 3}R have 12 μ\mu C and –3 μ\mu C charges, respectively, and are at a large distance from each other. They are now connected by a conducting wire. A long time after this is done the charges on S1 and S2 are respectively :

Multiple Choice Options

  • A 4.5 μ\mu C on both
  • B +4.5 μ\mu C and –4.5 μ\mu C
  • C 6 μ\mu C and 3 μ\mu C
  • D 3 μ\mu C and 6 μ\mu C

Step-by-Step Verified Solution

JEE Main 2020 (Online) 3rd September Morning Slot Physics - Electrostatics Question 151 English Explanation

q1 + q2 = 12 - 3 = 9 μ\mu C .....(1)

and V1 = V2

⇒\Rightarrow Kq12R3=Kq2R3{{K{q_1}} \over {{{2R} \over 3}}} = {{K{q_2}} \over {{R \over 3}}}

⇒\Rightarrow q1 = 2q2 .....(2)

Now puttion the value of (2) in (1), we get

2q2 + q2 = 9

⇒\Rightarrow 3q2 = 9

⇒\Rightarrow q2 = 3 μ\mu C

⇒\Rightarrow q1 = 6 μ\mu C

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