Register to reply

Maximum potential (coaxial cable)

by weesiang_loke
Tags: cable, coaxial, maximum, potential
Share this thread:
weesiang_loke
#1
Mar23-11, 08:32 AM
P: 33
1. The problem statement, all variables and given/known data
Given a coaxial cable with outer conductor of radius b, and inner conductor of radius a. Prove that maximum potential is obtained when a = b /e, e is base of natural log.

2. Relevant equations
gauss law, ...


3. The attempt at a solution
By using Gauss Law,
for a < r < b,
i have E = 2*k*[tex]\lambda[/tex] / r, where [tex]\lambda[/tex] = Q/L

then the potential difference, V= [tex]\int[/tex] E dr
V = 2*k*[tex]\lambda[/tex] ln (b/a),

but i am not sure how to continue by differentiating V wrt a.
Help me pls...
Thank you.
Phys.Org News Partner Science news on Phys.org
Climate change increases risk of crop slowdown in next 20 years
Researcher part of team studying ways to better predict intensity of hurricanes
New molecule puts scientists a step closer to understanding hydrogen storage
weesiang_loke
#2
Mar23-11, 08:47 PM
P: 33
Anyone pls help ......


Register to reply

Related Discussions
Coaxial Cable Introductory Physics Homework 6
Capacitance of coaxial cable Introductory Physics Homework 5
Coaxial cable? Introductory Physics Homework 2
Coaxial cable General Physics 0
Vector potential in a coaxial cable Advanced Physics Homework 5