Particles A and B, each carrying a charge of 2.0 nC , are at the base corners of
ID: 1434547 • Letter: P
Question
Particles A and B, each carrying a charge of 2.0 nC , are at the base corners of an equilateral triangle 1.5 m on a side.
Part A: What is the potential (relative to zero at infinity) at the apex of the triangle?
Part B: How much work is required to bring a positively charged particle carrying a charge of 5.0 nC from infinity to the apex if A and B are held fixed?
Part C: Calculate the electric potential energy for the triangular charge distribution.
Part D: What is the potential (relative to zero at infinity) at the apex of the triangle if particle B is replaced by a particle carrying a charge of 3.0 nC?
Part E: How much work is required to bring a positively charged particle carrying a charge of 5.0 nC from infinity to the apex if particle B is replaced by a particle carrying a charge of 3.0 nC and A and Bare held fixed?
Part F: Calculate the electric potential energy for the new triangular charge distribution.
Explanation / Answer
A) potential due to a point charge = kq/r
V = [ 9 x 10^9 x 2 x 10^-9 / 1.5 ] + [ 9 x 10^9 x 2 x 10^-9 / 1.5 ]
v = 24 volt
B) work done = q V = 5 x 10^-9 x 24 = 1.2 x 10^-7 J
C) potential energy of two charge set = kq1q2 / d
there will be 3 sets of charge .
PE = [9x 10^9 x 2 x 10^-9 x 5 x 10^-9 / 1.5 ] + [9x 10^9 x 2 x 10^-9 x 5 x 10^-9 / 1.5 ]
+ [9x 10^9 x 2 x 10^-9 x 2 x 10^-9 / 1.5 ]
PE = 1.44 x 10^-7 J
D)
V = [ 9 x 10^9 x 2 x 10^-9 / 1.5 ] + [ 9 x 10^9 x -3 x 10^-9 / 1.5 ]
= - 6 volt
E) W = -6 x 5 x 10^-9
= - 3 x 10^8 J
F) PE = [9x 10^9 x 2 x 10^-9 x 5 x 10^-9 / 1.5 ] + [9x 10^9 x 2 x 10^-9 x -3 x 10^-9 / 1.5 ]
+ [9x 10^9 x -3 x 10^-9 x 5 x 10^-9 / 1.5 ]
PE = - 6.6 x 10^-8 J