Manipal MET2011PhysicsElectrostatics
A charge of 10⁻⁹ C is placed on each of the 64 identical drops of radius 2 cm . They are then combined to form a bigger drop. Its potential will be
Options
- A7.2 10^3 ~V
- B7.2 10^2 ~V
- C1.44 10^2 ~V
- D1.44 10^3 ~V
Correct answer
A. 7.2 10^3 ~V
Step-by-step solution
Volume of bigger drop = volume of 64 small drops i.e., 4 3 R^3=64 4 3 r^3 or R=4 r Potential on small drop V₁= 1 4 ₀ q r Potential on bigger drop aligned V₂ & = 1 4 ₀ 64 q R V₂ & = 1 4 ₀ 64 q 4 r & = 9 10^9 64 10⁻⁹ 4 2 10⁻² & =7.2 10^3 ~V aligned