# physics

A 10uf capacitor is charged from a 30v supply and then connected across an uncharged 50uf capacitor.Calculate
a. The final potential difference across the combination
b. The final and initial energies

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1. Q initial=10u*30=300u
That charge then redistriubtes (equivalent capacitor=60uf
C=Q/V
V=Q/C-300u/60=5volts

energy initial=1/2 CV^2=1/2 *10u*900=4500u Joules

energy final=1/2 CV^2=1/2 60u*5^2
30*25u=750u

So where did the energy go? A paradox? http://hyperphysics.phy-astr.gsu.edu/hbase/electric/capeng2.html#c4

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2. am not understanding the working well

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3. Good

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4. 👍🏻👍🏻👍🏻

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