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DODGEVIPER13 said:Yah I think it goes from a at t<0 and moves to b at t=0
DODGEVIPER13 said:the 60 ohm resistor and capacitor is as well right?
DODGEVIPER13 said:ok so are the 40 ohm and 60 ohm resistors in parallel with each other and then the 120 ohm one is in series with that giving a total R=144 ohm so therefore I= 30/144=.208 A??
DODGEVIPER13 said:could I use my current divider as I did earlier multiplied by the total current in the b portion only so .208(60/100)=.1248A and the current through the 40 ohm resistor is 30/40=.75A then using my charascteristic equation I get .1248+.6252e^(-t/20).
DODGEVIPER13 said:so is the capacitor voltage 30 volts because 40(60/(60+20))=30 V or should I use an equation to find for the capacitor voltage?
DODGEVIPER13 said:at t>0 the eventual value would be this 5+25e^(-t/20) you said I already calculated it so I can only assume this is what you are referring to?
DODGEVIPER13 said:ok well as t approaches infinity I have Vc= 5 V so if this is true 5 volts is what goes across the 40 ohm resistor. therefore the amperage across the 40 ohm is I=5/40=.125A.
DODGEVIPER13 said:Hmmm it calls for an expression so I know it is of the form I(t)= .125+Ae^(-t/20)
DODGEVIPER13 said:oh so are you saying that I(t)=Vc(t)/40 which would give i(t)= .125+.625e^(-t/20)
DODGEVIPER13 said:ok so the answer should be:
i(t)=.1875A for t<0
i(t)=.125+.625e^(-t/20)A for t>0
An RC (resistor-capacitor) circuit is a type of electrical circuit that consists of a resistor and a capacitor connected in series or parallel. It is commonly used in electronic devices to control the flow of electric current and store energy.
To calculate the voltage and current in an RC circuit, you can use Ohm's Law (V=IR) and the equation for the charge on a capacitor (Q=CV), where V is voltage, I is current, R is resistance, C is capacitance, and Q is charge. You may also need to use Kirchhoff's laws to analyze more complex RC circuits.
The voltage and current in an RC circuit are affected by the values of the resistor and capacitor, the frequency and amplitude of the input voltage, and the initial conditions of the capacitor (i.e. the amount of charge on it). The type of circuit (series or parallel) and the presence of other components can also impact the voltage and current.
The phase angle, which represents the relationship between the voltage and current in an AC circuit, can affect the voltage and current in an RC circuit. In a purely capacitive circuit, the current leads the voltage by 90 degrees, whereas in a purely resistive circuit, the current and voltage are in phase. In an RC circuit, the phase angle will be somewhere in between these two extremes, depending on the values of the resistor and capacitor.
RC circuits are commonly used in electronic devices such as filters, timing circuits, and oscillators. They can also be found in power supplies, audio amplifiers, and electronic ignition systems. In the field of medicine, RC circuits are used in medical devices such as pacemakers and defibrillators. They are also used in wireless communication systems to filter out unwanted signals.