Max Harge on a Capacitor in LC Circuits

AI Thread Summary
The discussion revolves around calculating the maximum charge on a capacitor in an LC circuit with given values for capacitance and inductance. The formula Q=CV was initially used, but the result of 3e-9 was incorrect. The user attempted multiple methods, including energy equations and angular frequency calculations, but consistently arrived at the same incorrect charge. A suggestion was made to consider significant figures, leading to a recalculation that corrected the charge to 3.1e-9. Ultimately, the user resolved the issue by using a different calculator to verify the correct answer.
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Homework Statement


An oscillating LC circuit consisting of a 1.2 nF capacitor and a 3.3 mH coil has a maximum voltage of 2.6 V.
(a) What is the maximum charge on the capacitor?


Homework Equations


Q=CV


The Attempt at a Solution


I tried Q=CV but this did not work I got the answer 3e-9 when I plugged in but this did not work. I have also tried doing it the long way by solving for energy using .5Li^2 = .5CV^2 then solving for i. Then I solved for w by using ω=1/(√LC) and the solved for the period by using T=2∏/ω which after you find it you can divide by 4 to get time when you can plug in time, angular frequency, and current max to the equation I(max) = -ωQ(max)sin(ωt) this gave me 3e-9 as well which is not correct. The numbers I got for I(max) = .00155692, ω=502518.9076, time=.000003126. Finally I have tried this which I found online Q=(energy of capcitance)V this gave me 1e-8 this did not work either. I double checked the numbers in my calc and they were correct I don't understand!
 
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Is it possible that you're being tripped up by required significant figures? Was your charge really 3E-9, or should it be 3.1E-9?
 
I am going to try another calulator mine seems to be off
 
LOL thanks man that worked and I checked it with a new calc.
 
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