shyguy79
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Hi guys, doing an assignment question
A spherical conductor filled with air with a radius of 2cm is supported in the air. Electrical breakdown occurs when the electric field reaches 3.0 x 10^6 Vm^-1
(a) What is the maximum charge that can be placed on the sphere?
(b) What is the value of the potential on the surface of the conductor when carrying maximum charge
E(r) = 1/4∏ε0 x Q/R^2 where 1/4∏ε0 = 9x10^9, Q = charge and R^2 =radius of sphere 0.2m
V(r) = 1/4∏ε0 x Q/R
Ok, so for the (a) then using the equation for electric field E(r) rearranged for Q
Q = (E(r) x R^2)/9x10^9 =(3.0 x 10^6 Vm^-1 x 0.2^2)/9x10^9 = 13μC
Seems realistic? Just not sure of the next bit...
V(r) = 1/4∏ε0 x Q/R = 9x10^9 x (13x10-6C / 0.2m) = 585kV
585kV? Something has gone wrong... is this a viable answer or should I be taking into account the area of the sphere...
Homework Statement
A spherical conductor filled with air with a radius of 2cm is supported in the air. Electrical breakdown occurs when the electric field reaches 3.0 x 10^6 Vm^-1
(a) What is the maximum charge that can be placed on the sphere?
(b) What is the value of the potential on the surface of the conductor when carrying maximum charge
Homework Equations
E(r) = 1/4∏ε0 x Q/R^2 where 1/4∏ε0 = 9x10^9, Q = charge and R^2 =radius of sphere 0.2m
V(r) = 1/4∏ε0 x Q/R
The Attempt at a Solution
Ok, so for the (a) then using the equation for electric field E(r) rearranged for Q
Q = (E(r) x R^2)/9x10^9 =(3.0 x 10^6 Vm^-1 x 0.2^2)/9x10^9 = 13μC
Seems realistic? Just not sure of the next bit...
V(r) = 1/4∏ε0 x Q/R = 9x10^9 x (13x10-6C / 0.2m) = 585kV
585kV? Something has gone wrong... is this a viable answer or should I be taking into account the area of the sphere...