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10.0 points A 35pF capacitor is charged to 5kV and then removed from the battery and connected in parallel to an uncharged 55pF capacitor. What is the new charge on the second capacitor? Answer in units of nC.

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Final answer:

The new charge on the second capacitor, when a 35pF capacitor charged to 5kV is connected in parallel with an uncharged 55pF capacitor, is 275nC.

Step-by-step explanation:

The question involves a physics concept called charge conservation in capacitors. When two capacitors are connected in parallel, the total charge is conserved. To find the new charge on the second capacitor when a 35pF capacitor charged to 5kV is connected in parallel with an uncharged 55pF capacitor, we use the formula Q = CV, where Q is the charge, C is the capacitance, and V is the voltage. Initially, the charge on the 35pF capacitor is Q = C1 V1 = 35pF * 5000V = 175µC. After the connection, this charge redistributes over the total capacitance (Ctotal = C1 + C2).

The voltage across both capacitors after connection is Vnew = Q / Ctotal. Therefore, the charge on the second capacitor (55pF) at this new voltage is Q2 = C2 Vnew. Here, Vnew is the same as before since they are in parallel, so the new charge Q2 would be 55pF * 5000V = 275µC. To convert this into nanocoulombs (nC), we multiply by 1000, getting Q2 = 275nC.

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