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Vg = 76.0V , R1 = 25.0kΩ , R2 = 13.0kΩ , R3 = 88.0kΩ , and C = 56.0μF
I did 76*(R2/[R1+(R2*R3/(R2+R3)]) and got 27.2V and it keeps on telling me that i have a rounding error
Vg = 76.0V , R1 = 25.0kΩ , R2 = 13.0kΩ , R3 = 88.0kΩ , and C = 56.0μF
I did 76*(R2/[R1+(R2*R3/(R2+R3)]) and got 27.2V and it keeps on telling me that i have a rounding error
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initially, the switch is set so that the voltage only sees {R1,R2} and the capacitor can be assumed to be fully charged, meaning that there is no current flowing through it.
so the current through R3 is zero and the circuit is just (R1,R2) in series, and because the cap is in parallel with R2, the voltage across it must be the same as the voltage across R2.
{R1,R2} forms a voltage divider -- so it should be straightforward to complete the analysis with all that in mind.
your original analysis cannot be correct because of the presence of R3 in the solution, so the computer grading the effort is incorrectly identifying it as a rounding error -- for if you do the formal error analysis of your answer compared to the correct one, you should find the erroneous R3 contribution will definitely appear to look like a rounding error relative to the correct solution.
so the current through R3 is zero and the circuit is just (R1,R2) in series, and because the cap is in parallel with R2, the voltage across it must be the same as the voltage across R2.
{R1,R2} forms a voltage divider -- so it should be straightforward to complete the analysis with all that in mind.
your original analysis cannot be correct because of the presence of R3 in the solution, so the computer grading the effort is incorrectly identifying it as a rounding error -- for if you do the formal error analysis of your answer compared to the correct one, you should find the erroneous R3 contribution will definitely appear to look like a rounding error relative to the correct solution.