rc (for "run commands") is the command line interpreter for Version 10 Unix and Plan 9 from Bell Labs operating systems. It resembles the Bourne shell, but its syntax is somewhat simpler. It was created by Tom Duff, who is better known for an unusual C programming language construct ("Duff's device").A port of the original rc to Unix is part of Plan 9 from User Space. A rewrite of rc for Unix-like operating systems by Byron Rakitzis is also available but includes some incompatible changes.
Rc uses C-like control structures instead of the original Bourne shell's ALGOL-like structures, except that it uses an if not construct instead of else, and has a Bourne-like for loop to iterate over lists. In rc, all variables are lists of strings, which eliminates the need for constructs like "$@". Variables are not re-split when expanded. The language is described in Duff's paper.
Homework Statement
Find v(t) after t=0, when the switch moves up
need to know if i did this right.. V(C1)=V(C2)=10V (this is same for t=0- and 0+)
V(infinity)=0V (no voltage source)
T=RC=100k(ohm)*(4uF)=0.4 sec. (i got the 4uF by putting the 2 caps. in parallel with each other, because they...
Homework Statement
I'm trying to use the equation for charging capacitor that's discharging, and I can't get the answer right. On the calculator it keeps showing as 1.Homework Equations
I(t) = -(1.96) [e^((-9.0*10^(-6)) / (1300)(2.0*10^(-9)))]The Attempt at a Solution
My problem is that the...
Homework Statement
after having been in position 1 for a long time, the switch was moved to position 2 at t=0. determine:
a) i-c(0-) and vc(0-)
b) i-c(0) and v-c(0)
c) i-c(infinity) and v-c(infinity)
d) v-c(t) for t>=0
e) i-c(t) for t >=0Homework Equations
The Attempt at a Solution
not sure...
Homework Statement
For the circuit below, the switch has been closed for a period of time long enough for steady state conditions to have been reached.
a: Determine the time constant before the switch is opened
b: Determine the time constant after the switch is closed
c: Determine the...
the attached file is the question
I know the time constant after opening the switch
but how can i know the time constant when the switch is on?
This is NOT the classic initial and AFTER A LONG LONG LONG Time question
How can i know the potential of C in t=2s ?
What is the equation...
[b]1. You are investigating how energy is transferred in circuits with batteries, resistors, and a capacitor. First you take an uncharged capacitor and connect it in a simple series circuit with a resistor and a battery. You wait for the circuit to reach a steady state. After a steady state is...
Homework Statement
Please look at the attachment for the circuit.
The question is this:
The switch has been closed for a long time. It is then opened. How long does it take for the potential across the 4μF capacitor to fall to half of its initial value?
Homework Equations
V =...
Homework Statement
A circuit is constructed with four resistors, one capacitor, one battery and a switch as shown. The values for the resistors are: R1 = R2 = 52 Ω, R3 = 41 Ω and R4 = 129 Ω. The capacitance is C = 62 μF and the battery voltage is V = 24 V.
1) The switch has been open for a...
In a series RC circuit, the current flows until the voltage of the capacitor equals that of the source so that the two voltages oppose each other and there's no net flow.
In a parallel circuit, the current indeed does stop flowing through the branch the capacitor is attached to (after the...
http://i.imgur.com/ZCcaZpq.png
I have the solution manual, so this is more just a question of why, rather than what.
I understand that with the switch open:
vA = 3v
vB = vC = 0v
i0 = 0.25 mA
When the switch closes it creates a short that makes the two 6kΩ resistors irrelevant...
So we're covering RC circuits in my physics class and I'm having some trouble with the concepts.
When you have a circuit with a resistor and a battery, current passing through the resistor produces a voltage drop. If the battery is zero for our potential, the battery imbues the circuit with...
Homework Statement http://imageshack.us/a/img831/8798/homeworkprobsg31.jpg Assuming that the switch has been in position #1 for a long time; at t = 0 the switch is moved to position #2.
Calculate the current i(t) for t>0.Homework Equations
Q = CV
V = IR
V(t) = -V0*e-t/RC
(V0 is the...
Homework Statement
What is Q(∞), the charge on the capacitor after the switch has been closed for a very long time?
a circuit, whose image is attached, has known values for the resistors : R1 = R2 = 72 Ω, R3 = 101 Ω and R4 = 79 Ω, is C = 56 μF, V = 24 V.
Homework Equations
kirchoff's laws...
Homework Statement
i tried using the usual Q=VC to answer this question for a multiloop RC circuit, "What is Q(∞), the charge on the capacitor after the switch has been closed for a very long time?" and my answer was wrong. clearly, i can't find Qmax because the resistors contribute to the...
Homework Statement
A circuit is constructed with four resistors, one capacitor, one battery and a switch as shown. The values for the resistors are: R1 = R2 = 22 Ω, R3 = 91 Ω and R4 = 129 Ω. The capacitance is C = 40 μF and the battery voltage is V = 12 V. The positive terminal of the battery...
Homework Statement
Consider a series RC circuit with R = 151 Ω and an unknown capacitor C as shown below.
http://www.flickr.com/photos/67342906@N0…
The circuit is driven by an alternating electromotive force with εRMS = 174 V at a frequency of f = 7.70 Hz. The current in the...
Given that:
It=3<110°A
Vt=120<40°V and ω=314.2rad/sec
Find the impedance of the series ciruit elements in rectangular form and state the type and value of the respective elements.
I have found the impedance and know that it is a RC circuit as current 110° is leading voltage 40°.
How do...
Homework Statement
what is the forced response for Rc cct. and how to derive it??
Homework Equations
I know that the forced response in RL cct. is :
i = cos (ωt - tan^-1
we start from :
Vm cos (ωt) = Ri + L
and
i = I am cos (ωt-θ)
Can anyone help please!
Hello, I'm trying to analyze the RC circuit... specifically a low-pass filter, so the set up is voltage source to resistor to capacitor, and the voltage source provides an oscillating voltage Vin, whereas I measure Vout across the capacitor.
I think I'm getting confused between two different...
Homework Statement
This isn't a problem from a textbook, but it is homework.
For a lab in class, we worked with simple RC circuits on breadboards. The strange thing I noticed is that the capacitor always charges faster than it discharges. I know that the Time constant should be T=RC, so I...
RC circuits -- questions about the solution
Homework Statement
First of all , greetings from Peru and thank you to all the people who help another people here,taht's awesome , please help me with this guys... Here's the statement
The solution is
My questions:
ok my question is about the...
Homework Statement
A 200mF capacitor is charged to 10V and then discharged through a 250kW resistor. Calculate the potential difference across the capacitor at intervals of 10s
The Attempt at a Solution
Firstly, I am completely unsure how to obtain a value for R or C from a 'kW'...
Homework Statement
Find the phase angle between the input and output voltages in the following two circuits - in each case state whether the output leads or lags the input voltage.
The second circuit is the same but the capacitor and the resistor are switched around.
Homework Equations...
I have a series rc circuit.
80 v battery, capacitor1, resistor1: 10M ohm, capacitor 2, then back to the negative end of the battery.
Capacitor 1 and 2 are equal, after a certain time, the voltage on each capacitor is 40.0v. What is the capacitance of each capacitor?
Thanks!
I'm trying to use a second order passive RC filter to attenuate noise in a thermocouple signal. I've heard that using two passive RC filters in series can generate "loading" effects. I'm not sure exactly what this means, except for the output response is different from the theoretical...
Homework Statement
In the following transient circuit, assume at t<0, the circuit is at steady state.
Find i0(t) for t>0
http://sphotos-b.xx.fbcdn.net/hphotos-ash3/c0.0.241.241/p403x403/521743_510378412315012_79982992_n.jpg
Homework Equations
The Attempt at a Solution
First...
Homework Statement
If you have this RC Circuit (ignore the yellow path of current):
http://i.imgur.com/Mi2bj.png
When you are calculating time constant=RC, what would you use for R?
R1=100 ohms, or Req=300 ohms
Homework Equations
time constant = RC
The Attempt at a Solution...
Homework Statement
Consider the circuit below, where C1=80mF, C2=30mF, R=50ohms and E=5V.
At t=0, both capacitors are uncharged - so it's charging.
The circuit is in series, with E ---> C1 ---> C2 ---> R ---> (back to) E
a) Find the time constant.
b) The initial potential...
Homework Statement
I know that in a RC DC circuit the time constant is R*C. But what about a RC AC circuit, is it the same time constant?
Same goes with RL AC circuit, is the time constant R/L?
Thanks!
Homework Statement
Given the drawing, calculate the current going through the 2Ω Resistor and then calculate the difference in electric potential from point a to b.
Homework Equations
V = IR
juction rule:
ƩI = 0 = Iin - Iout
ƩV = 0
The Attempt at a Solution
Well, I attempted to draw all the...
Homework Statement
In the circuit shown in the following figure(Figure 1) the capacitor has capacitance 20 microF and is initially uncharged. The resistor R_0 has resistance 12 Ohms . An emf of 90.0V is added in series with the capacitor and the resistor. The emf is placed between the...
Homework Statement
Determine the value of the current labeled i and the voltage labeled v at t=0+, t= 1.5 ms, and t = 3.0 ms.
Homework Equations
Ohm's law: v = i *r
Decay in source free RC Circuit v(t) = v@0 * e^(-t/RC)
The Attempt at a Solution
i(0-) = 0.1 A.
Therefore,
v across 200 ohm =...
what is the unit step response of a high pass RC filter ?
I want to calculate using transfer function approach.
My solution :
Y(s)/X(s) = RCs/(1+sRC)
X(s)=1/s
Y(s)=RC/(1+sRC)
taking inverse laplace transform we should get
y(t)=exp(-t/RC)
But if we consider Y(s)=RC/(1+sRC)
RCsY(s)...
Homework Statement
An RC circuit has EMF=12.0V, R=15 kΩ and C=3.8 μF. How long does it take for energy stored in the capacitor to reach 65% of its maximal value?
Homework Equations
1) Q = Cε
2) Q X .65 = desired charge
3) q(t) = Q(1 - e-t/RC)
The Attempt at a Solution
This is...
Send telemetry from an RC airplane from 2 miles up
here is what I am trying to do.
I got a Nerdkit to learn the basics of electronics(I'm not an engineer, just starting) and I need a project to develop and since I'm passionate about airplanes and remote data sending(?) I want to tackle this...
Homework Statement
Relevant infor
V(out) stands for the voltage divider I believe
The Attempt at a Solution
I am just going to get the equation first.
For the first part, applying the loop rule I got
12 - 10^5q' - 10^7 q = 0 with q(0) = 0. Solving I get
Q =...
Homework Statement
When the cehicl stop's in the team's pit stop, consider the time as being t=0. If the potential difference between the car and ground is 30kV, the car-ground capacitance is 500pF and the resistance of each tyre is 100Gohm, determine the time it takes for the car to discharge...
Homework Statement
I would like to derive the equation Vc=Vss+(Vi-Vss)*e^(-t/RC)
Vss is the steady state voltage
Vi is the initial capacitor voltage
Vc is the capacitor voltage
The Attempt at a Solution
I tried to find solution using laplace transform. E=iR+1/c∫idt.
Taking laplace...
Homework Statement
I need to prove that RC=(VT/2 delta V)
Select the circle components of Charging and discharging of a capacitor
Measure the resistance of resistor with a multimeter
When you run a different frequency the cycle time change
run different frequency that T<<tao, T=tao...
I'm still learning about this, but it seems that an RC circuit performs the same function as an op amp integrator (http://www.electronics-tutorials.ws/opamp/opamp_6.html). In other words, they both can be used as integrators/low pass filters.
If this is true, why would anyone bother with an...
Hey,
Actually I am working on my research project and facing a problem on solving a simple series RC circuit. But the problem is the Resistance and capacitance of the circuit is increasing with the time, and I am working on finding the value of R and C at the steady state as well as the time...
Homework Statement
For the below circuit, the switch was open for a long time. Find the current Ia(t) for t>0. All capacitors are initially uncharged.Homework Equations
Complete response of a capacitor: v(t) = Voc + (v(0) - Voc)e^(-t/τ)
Combining parallel capacitors: summation
Current through a...
Signal flow graph, describing a RC circuit?
Hi, guys. This is my first post on this forum!
I'm trying to understand this example in my textbook.
The current and voltage equations are:
where G=1/R, Z(s)=1/Cs, and I1(s)=I1
Then the text says the following signal flow graph can be obtained:
And...
I've been experimenting for hours, and my LED still won't light correctly when this method is used, and the fluke 87 reads voltage on the circuit in a non-logical way. Can you help? Here's what I have set up when using an online calculator:
Time delay: 2000 milliseconds
Power supply: 15v...
Hello,
I am working on a creating the characteristic equation (in general terms) of the voltage (and current, but not as important) for the capacitor in a RC connected to a LR. The RC circuit is initially charge (say has been connected to a power supply for all time before t = 0) and at t = 0 a...
Supposing we have an RC circuit (see figure)
As we increase R, what will happen to the visualized signal of E and V(capacitor) and V(resistor)?
And a general question about measuring the (Tao) [the one that equals to RC] BUT FROM THE OSCILLOSCOPE..
They mentioned it is the time for...
I'm looking to put motors into a scale model plane and was just wondering whether the motors I've picked will be ok and what sort of supply voltage I would need.
I'm going to use 4 of these.7
Specs:
Operating Voltage: 3.7V
Diameter: 7.0mm
Length: 25.5mm
Output Shaft Diameter...
I'm having a hard time visualizing what happens on the plates of the capacitor in series with a resistor in a high pass filter circuit. When the input to the capacitor is high, assuming a sine wave (say +5V) what happens on the opposite plate of the capacitor (Vout)? Should the output follow the...