JEE PYQ: Electrostatics Question 11
Question 11 - 2021 (25 Feb Shift 2)
Two identical conducting spheres with negligible volume have $2.1$ nC and $-0.1$ nC charges, respectively. They are brought into contact and then separated by a distance of 0.5 m. The electrostatic force acting between the spheres is ______ $\times 10^{-9}$ N.
[Given: $\frac{1}{4\pi\varepsilon_0} = 9 \times 10^9$ SI unit]
Show Answer
Answer: 36
Solution
After contact, each sphere has $\frac{2.1 + (-0.1)}{2} = 1$ nC. $F = \frac{kq^2}{r^2} = \frac{9 \times 10^9 \times (10^{-9})^2}{0.25} = 36 \times 10^{-9}$ N.
BETA
