Home
Class 12
PHYSICS
Three parallel metalic plates each of ar...

Three parallel metalic plates each of area `A` are kept as shown in figure and charges `q_1,q_2` and `q_3` are given to them. Find the resulting charge distribution on the six surfaces, neglecting edge effects as usual,

Text Solution

Verified by Experts

The plate separations do not affect the distribution of charge in this problem.
In the figure
`q_0=q_1-q_a,q_d=q_2-q_c`
`and q_f=q_3-q_e`
electric field at point P is zero because this point is lying inside a conductor.
`E=0`

At `P` charge `q_a` will give an electric field towards right. All other charges `q_0, q_c.`.........etc. will give electric field towars left. So,
`1/(2Aepsilon_0)[q_a-(q_1-q_1)-q_c-(q_2-q_c)-q_e-(q_3-q_e)]=0`
or `2q_a-q_1-q_2-q_3=0`
or `q_a=(q_1+q_2+q_3)/2`
similarly the conditionn
`E_R=0`
will give the result
`q_f=(q_1+q_2+q_3)/2`
from here we may conclude that half of the sum of all charges appears on each of the two outermost surfaces of the system of plates.
Further we have a condition.
`E_Q=0`
`1/(2Aepsilon_0)[q_q+(q_1-q_a)+q_c-(q_2-q_c)-q_e-(q_3-q_e)]=0`
or `q_1+2q_c-q_2-q_3=0`
`:. q_c=(q_2+q_3-q_1)/2`
`q_b=q_1-q_a=(q_1-q_2-q_3)/2=-q_c`
similarly, we can show that
`q_d=-q_e`
from here we can find another important resultant that the pairs of opposite surfaces like `b,c`, and `d,e` carry equal and opposite charges.
Promotional Banner

Topper's Solved these Questions

  • CAPACITORS

    DC PANDEY|Exercise Exercise|155 Videos
  • CAPACITORS

    DC PANDEY|Exercise OBJECTIVE_TYPE|1 Videos
  • ATOMS

    DC PANDEY|Exercise MEDICAL ENTRANCES GALLERY|42 Videos
  • COMMUNICATION SYSTEM

    DC PANDEY|Exercise Subjective|11 Videos

Similar Questions

Explore conceptually related problems

The value of charge q_1 ,q_2 and q_3 as shown in the figure are

Three identical metallic plates, each of area A, are kept at small separations as shown. Initially, charge Q, 3Q and 3Q are given to the plates A, B and c, respectively. Now, both the switches S_(1) and S_(2) are closed simultaneously. Then Charge flown through S_(1) and S_(2) are

Two metallic plates are kept parallel to one another and charges are given to them as shown in figure. Find the charge on all the four faces.

Three very large plate are given charges as shown in the figure, if the cross -sectional area of each plate is the same the final charge distribution on plate C is

Two conducting plates A and B are placed parallel to each other. A is given a charge. Q_1 and B a charge Q_2 . Find the distribution of charges on the four surface.

Some isolated metal plates with large surface areas are kept parallel to each other and total charges on each plate are as shown. Find the charge appearing on the surfaces of plates. (a)

Three identical conducting plain parallel plates, each of area A are held with equal (/ between successive surfaces. Charges 2Q , and 3Q are placed on them. Neglecting edge effects, find the Charge on the left face of the middle plate

Three charges -q_1 , +q_2 and -q_3 are placed as shown in the figure. The x-component of the force on -q_1 is proportional to

The three small spheres as shown in figure carry charges q_1 = 4nC, q_2 = -7.8nC and q_3 = 2.4nC . Find the net electic flux through each of the following closed surfaces shown in cross section in the figure. a. S_1 b. S_2 c. S_3 d. S_4 e. S_5 . Do your answers to parts from (a) to (e) depend on how the charge is distributed over each small sphere? Why or why not? .

Three identical metal square plates of surface area A of each side is arranged as shown in the figure.Plates 1 2 and 3 are given charges +20, -Q and -Q respectively. Find out the correct options A) Charge on the two faces of the middle plate are -2Q and Q B) Charge on the two faces of the middle plate are -Q and 0 C) Charge on the two faces of the left most plate are zero and 2Q D) Charge on the two faces of the right most plate are -Q and zero