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Fuego
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If i take a 2microF capacitor charged to a p.d. of 50V, and a 3microF capacitor charged to 100V, and connect them in parallel with their positive plates connected,
a) what is the equivalent capacitance of this combintation?
b) what is the p.d. across each capacitor after they are connected?
c) what is the total energy stored by the capacitors?
d) why is there a loss of stored energy when the capacitors are connected (as opposed to when they are separate)?
Part a is pretty simple (i think!). you just add the capacitance of each capacitor to get 5microF, right?
Part b confuses me. I know that when capacitors are in parallel, the voltage is the same on each one, but I don't know how to find that voltage! Is it just 50V + 100V = 150V? Or is it the average of the two = 75V? Or something else?
For part C I guess i need to use the equation Energy stored = (1/2)CV^2, but for that I need to know the p.d. across the capacitors!
Part d: is it because energy is lost in the wires that connect the capacitors?
Thanks in advance!
a) what is the equivalent capacitance of this combintation?
b) what is the p.d. across each capacitor after they are connected?
c) what is the total energy stored by the capacitors?
d) why is there a loss of stored energy when the capacitors are connected (as opposed to when they are separate)?
Part a is pretty simple (i think!). you just add the capacitance of each capacitor to get 5microF, right?
Part b confuses me. I know that when capacitors are in parallel, the voltage is the same on each one, but I don't know how to find that voltage! Is it just 50V + 100V = 150V? Or is it the average of the two = 75V? Or something else?
For part C I guess i need to use the equation Energy stored = (1/2)CV^2, but for that I need to know the p.d. across the capacitors!
Part d: is it because energy is lost in the wires that connect the capacitors?
Thanks in advance!