JEE Main2011PhysicsElectrostaticsActual
Two identical charged spheres suspended from a common point by two massless strings of length I are initially a distance d(d< < 1) apart because of their mutual repulsion. The charge begins to leak from both the spheres at a constant rate. As a result the charges approach each other with a velocity v . Then as a function of distance x between them,
Options
- Av x⁻¹
- Bv x^ 1 / 2
- Cv x
- Dv x^ -1 / 2
Correct answer
D. v x^ -1 / 2
Step-by-step solution
At any instant of separation between charges is x . aligned & equilibrium condition = K Q ^2 x ^2 = x 2 & Q ^2= Cx ^3 & 2 Q dQ dt = C 3 x ^2 dx dt & dx dt x ^ 3 / 2 x ^2 x ^ -1 / 2 aligned