Guest

Two identical pith balls,each carrying a charge q,are suspended from a common point by two strings of equal length l1 &l2.find the mass of each ball if the angle between the strings is 2a in equilibrium.

Two identical pith balls,each carrying a charge q,are suspended from a common point by two strings of equal length l1 &l2.find the mass of each ball if the angle between the strings is 2a in equilibrium.

Grade:12

1 Answers

Arun
25750 Points
6 years ago
Dear Nikhil

Let the lengths of the two strings be equal to 'L'
The distance between the two pith balls will be, r = 2Lsinθ
now, here
electrostatic force = gravitational force
kq2/r2 = mgtanθ
or
kq2 / (2Lsinθ)2 = mgtanθ
or
m = kq2 / gtanθ(2Lsinθ)2
thus,
mass of each ball will be
m =  kcosθq2 / 4gL2(sinθ)3
 
Regards
Arun (askIITians forum expert)

Think You Can Provide A Better Answer ?

ASK QUESTION

Get your questions answered by the expert for free