ElectrostaticsHard
Question
An oil drop of mass M is found floating freely between the plates of a parallel plate condenser (which consists of two large metallic plates having equal and opposite charges), the plates being horizontal and the lower plate carrying a charge +Q. The area of each plate is A and the distance of separation between them is D. The charge on the oil drop must be (g is the acceleration due to gravity)
Options
A.
B.
C.
D.
Solution

Let the charge on oil drop be q, so in equilibrium :
qE = Mg
⇒ q =
⇒ q =
Create a free account to view solution
View Solution FreeMore Electrostatics Questions
An electric dipole is placed at the centre of a sphere. Mark the correct answer :...The capacitors C1,C3 ,C4 ,C5 have a capacitance 4μF each and C2 has capacitance 10μF. The effective capacitanc...If electric field is uniform, then the electric lines of forces are:...Three points charges are placed at the corners of an equilateral triangle of side L as shown in the figure :...In the fig. force on charge at A in the direction normal to BC will be :-...