- #1
Electric Circuit Differential equation help
- Thread starter Vossi
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SUMMARY
The discussion focuses on the derivation of terms 4Vc and 48 cos(60t) in the context of a first-order differential equation for an electric circuit. Participants express confusion regarding the values of resistance (R) and capacitance (C) and their implications on the circuit's behavior. The correct calculation for the time constant RC is established as 0.25 seconds, using R = 50K ohms and C = 5uF. The conversation highlights the importance of accurate parameter values in circuit analysis.
PREREQUISITES- Understanding of first-order differential equations in electrical circuits
- Knowledge of resistance (R) in ohms and capacitance (C) in farads
- Familiarity with the time constant calculation (RC)
- Basic principles of AC voltage sources and their representations
- Study the derivation of first-order differential equations in electrical circuits
- Learn about the impact of resistance and capacitance on circuit behavior
- Explore AC circuit analysis techniques, particularly phasor representation
- Investigate common mistakes in circuit parameter calculations and their effects
Electrical engineering students, circuit designers, and anyone involved in analyzing first-order electrical circuits will benefit from this discussion.
- #2
berkeman
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Welcome to PhysicsForums. 
It looks like they are just giving the equation for one case of the values of R, C and the driving voltage source...
Vossi said:
It looks like they are just giving the equation for one case of the values of R, C and the driving voltage source...
- #3
Mark44
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I don't get it, either.Vossi said:
The units for R and C should be in ohms and farads, so ##RC = (2 \times 10^3)(5 \times 10^{-6}) = 10 \times 10^{-3} = 10^{-2}## ohms-farads.
It's possible there is a mistake in the published answer.
- #4
DaveE
Science Advisor
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Yes, clearly RC=0.25 sec for the answer given. Like 50Kohm & 5uF, for example.
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