wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

Four point charges Q, q, Q and q are placed at the corners of a square of side 'a' as shown in the figure. Q q

Find the
(a) resultant electric force on a charge Q and
(b) potential energy of this system.

Open in App
Solution

(a) Force on charge Q at B due to charge q

F2=14πϵ0qQa2alongBY


F2=14πϵ0qQa2along BX

Resultant force, F=F21+F22alongBO

=2(14πϵ0qQa2)2=qQ24πϵ0 a2

Force due to charge Q=F3=14πϵ0QQ(2a2)along BO

Total resultant force = F+F3 along BO

=14πϵ02Qqa2+14πϵ0QQ2a2

=[14πϵ0Qa2(2q+Q2)]alongBO

(b) Total potential energy of the system,

U=14πϵ0[Qqa+Qqa+Qqa+Qqa+Qqa+QQ2a+qq2a]

=14πϵ0[4Qqa+Q22a+q22a]

=14πϵ0[4Qq+Q2+q22]


flag
Suggest Corrections
thumbs-up
48
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Coulomb's Law - Grown-up Version
PHYSICS
Watch in App
Join BYJU'S Learning Program
CrossIcon