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QJEEM20Phecd8: JEE Main 2020 Physics - Class 12 JEEM20Phecd8 Solution: Ten charges are placed on the circumference of a circle of…
Ten charges are placed on the circumference of a circle of radius R with constant angular separation between successive charges. Alternate charges 1, 3, 5, 7, 9 have charge (+q) each, while 2, 4, 6, 8, 10 have charge (–q) each. The potential V and the electric field E at the centre of the circle are respectively.
(Take V = 0 at infinity)
(Take V = 0 at infinity)
Multiple Choice Options
- A V = 0; E = 0
- B V=10q4πε0R; E=10q4πε0R2
- C V=10q4πε0R; E = 0
- D V = 0; E=10q4πε0R2
Step-by-Step Verified Solution
Net charge = 5q - 5q = 0
Potential of centre = V =
VC =
Let E be electric field produced by each charge at the centre, then resultant electric field will be
EC = 0, Since equal electric field vectors are acting at equal angle so their resultant is equal to zero.( From symmetric property of vector)
Potential of centre = V =
VC =
Let E be electric field produced by each charge at the centre, then resultant electric field will be
EC = 0, Since equal electric field vectors are acting at equal angle so their resultant is equal to zero.( From symmetric property of vector)