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menco
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Homework Statement
When the cehicl stop's in the team's pit stop, consider the time as being t=0. If the potential difference between the car and ground is 30kV, the car-ground capacitance is 500pF and the resistance of each tyre is 100Gohm, determine the time it takes for the car to discharge through the tires so that it is below the critical energy point of 50mJ
Homework Equations
Q=CV
T=RC
U=1/2 CV^2
Q=CV_in exp^-t/RC
The Attempt at a Solution
Q=CV
=(500x10^-12)(300x10^3)
=15x10^-6 C
T=RC
=(100x10^9)(500x10^-12)
=50s
U=1/2 CV^2
(50x10^-3)=1/2(500x10^-12)v^2
v=14142.1 v
Q=CV_in exp^-t/RC
t=-37.6s