.
Tcosθ=mg=10×10−6×10=10−4
Tsinθ=0.049×109×q2=F
tanθ==0.240.1=mgF
q=324210×10−8
0.95×10−8=21a×10−8
a=20
Two small spheres each of mass 10mg are suspended from a point by threads 0.5m long. They are equally charged and repel each other to a distance of 0.20m. The charge on each of the sphere is 21a×10−8C. The value of a will be ___.[Given g=10ms−2]
Held on 25 Feb 2021 · Verified 6 Jul 2026.
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