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Sphere Electricity Discharge

A uniform solid metal sphere of radius r has charge q. A spark suddenly connects the sphere and earth, causing the potential of the sphere to be reduced from V1V_1 to V2V_2. Calculate the energy dissipated in the spark.

Is there a way to do this without using capacitance? Thank you for help :smile:.
Why do you want to do it without capacitance?
Do you know the formula for the capacitance of a sphere?
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esrever
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Original post by old_teach
Why do you want to do it without capacitance?
Do you know the formula for the capacitance of a sphere?


Capacitance is 4πε0r4 \pi \varepsilon_0 r. I want to avoid using capacitance because since the question doesn't mention about capacitance, it just feels a bit random.

But considering the formula for energy is 2πε0r(V22−V12)2 \pi \varepsilon_0 r (V_2^2 - V_1^2), I don't think there is a easier way avoiding capacitance.

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