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Units and Measurement
Question
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A thin conducting ring and radius R is given charge +Q. The electric field at the centre O of the ring due to the charge on the part AKB of the ring is E. The electric field at the centre due to the charge on the part ACDB of the ring is 

  • 3E along KO

  • E along OK

  • E along KO

  • 3 E along OK

Answer

B.

E along OK


The fields at O due to AC and BD cancel each other. The field due to CD is acting in the direction OK and equal magnitude to E due to AKB.

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