11
.pdf
keyboard_arrow_up
School
University of Texas, Dallas *
*We aren’t endorsed by this school
Course
1301
Subject
Physics
Date
Dec 6, 2023
Type
Pages
3
Uploaded by Dylankid1234 on coursehero.com
RC Circuits
UTD physics - Spring 2023
1
PRE-LAB
NAME:___________________________
Course & Section _________________________
Feel free to draft your answers in pencil but remember that the pre-lab to be given to your TA must be in pen.
1.
How can you change the time constant if the capacitance of the circuit is fixed?
_________________________________________________________________________
[1]
2.
Initially, how large is
Δ𝑉𝑉
(
𝑡𝑡
)
Δ𝑉𝑉
(
0
)
? After an infinitely long time, what is the value of
Δ𝑉𝑉
(
𝑡𝑡
)
Δ𝑉𝑉
(
0
)
?
____________________________________________________________________________
_________________________________________________________________________
[2]
3.
Find
𝑡𝑡
1
/
20
in terms of
𝜏𝜏
. Will
𝑡𝑡
1
/
20
be changed if the time constant for the circuit is increased? If it
changes, explain how.
____________________________________________________________________________
____________________________________________________________________________
_________________________________________________________________________
[2]
4.
Now use
Δ𝑉𝑉
(
𝑡𝑡
)
Δ𝑉𝑉
(
0
)
=
𝑒𝑒
−
t
𝜏𝜏
to show that
𝑡𝑡
1
/
2
=
𝜏𝜏
ln2
.
____________________________________________________________________________
_________________________________________________________________________
[2]
5.
What is the ratio of the voltage at
𝑡𝑡
= 20
𝜏𝜏
to the initial voltage across the capacitor?
___________________________________________________________________________
_________________________________________________________________________
[2]
Since the ? = ??, if capacitance is fixed, to changing the resistance will
change the time constant.
Initially
Δ()/Δ(0) = e^(-t/), if t=0 then Δ()/Δ(0) = e^(-0/) = 1. After an infinitely
long time,
Δ()/Δ(0) = e^(-
∞/?) = 0
When the time constant of a circuit is increased, it results in a
proportional increase in the time taken for the circuit to reach a specific
state or achieve a certain behavior. In other words, a longer time
constant corresponds to a longer time duration for the circuit to respond
or settle to a new condition.
The ratio of the voltage at ? = 20? to the initial voltage across the capacitor is
given by 1 - ??^(
−20),
where ? is the time constant of the RC circuit.
The relationship
Δ()/Δ(0) = e^(-t/) implies that 1/2, the time at which the voltage
across the capacitor decreases to half of its initial value, is equal to ? times the
natural logarithm of 2, or ?1/2 = ?ln2.
NEEL BANSAL
2126.102
RC Circuits
UTD physics - Spring 2023
2
6.
How can the sum of voltages be a constant when
𝑽𝑽
𝑪𝑪
<
𝑽𝑽
𝑨𝑨
?
____________________________________________________________________________
_________________________________________________________________________
[2]
7.
Identify the parts of the cycle at which the current is smallest.
_________________________________________________________________________
[1]
8.
Calculate
the approximate time constant for circuit one.
_________________________________________________________________________
[1]
9.
…what approximate frequency corresponds to
T
= 20
τ
?
___________________________________________________________________________
_________________________________________________________________________
[1]
10.
Will this decay still be an exponential function of time? Will the time constant have changed? Explain.
____________________________________________________________________________
____________________________________________________________________________
_________________________________________________________________________
[2]
11.
Use the points selected to find the time constant;
_________________________________________________________________________
[1]
12.
Here is another decay: calculate the time constant using the points selected.
_________________________________________________________________________
[1]
In certain dynamic situations, such as during charging or discharging processes, or
due to changes in circuit parameters or input conditions, the sum of voltages in a
circuit can be a constant even when the voltage across a capacitor (VCC) is less than
the voltage across an inductor (VLL).
In an AC circuit with an inductive element, such as an inductor, the current is
smallest at the points of the cycle where the voltage is at its peak due to the
inductor's resistance to changes in current. These points, commonly referred to
as "zero crossing" points, have the highest rate of change of voltage and result
in the smallest current.
Time constant = 0.002 sec
.T=20*tau=20*0.002 =0.04 seconds then
frequency=1/T=25 Hz
The decay will still be exponential and time constant will also remain the same as
R*C.only the time at
which the curve starts changes.This will still be exponential, as it is
exponential everywhere in the V-t graph.The time constant is still the same, as it follows
the same shape.
The time constant is
τ=4.2099
∗10−2 s−4.0348∗10 −2 s=0.1751∗10−2
s
=8.1478
∗10−2s−8.0262∗10−2s=0.1216∗10−2s
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help
Related Questions
For the circuit in fig.11.78
composed of standard values:
Determine the time constant.
Write the mathematical expression for the current It after the switch is closed
Repeat part (b) for VL and VR
Determine il and VL at one three- and five-time constants.
Sketch the waveforms of iL,VL and VR.
arrow_forward
Problem 10:
Part (a) Express the maximum voltage ΔVmax, in terms of Imax and Z.
ΔVmax = ______
Part (b) Calculate the numerical value of ΔVmax in volts.
ΔVmax = ______
Part (c) Calculate the numerical value of the rms current, Irms, in amps.
Irms = ______
Part (d) Calculate the numerical value of the rms voltage, ΔVrms in volts.
ΔVrms = ______
arrow_forward
The remaining circuit quantities may change instantaneously as required by Kirchhoff's rules. Calculate I1 , I2 , and I3 in amps immediately after the switch ( t = 0 + ), in that order. Finally, calculate Q in uC. (All currents in this and the following two should be positive.)
arrow_forward
What is IC,max(open), the current that flows through the capacitor whose magnitude is maximum during the time when the switch is open? A positive value for the current is defined to be in the direction of the arrow shown. in amps
arrow_forward
Explain the AC operation of electrodynamic instrument in detail.
arrow_forward
Can you show me how to work this? I’m thinking I’m getting confused on the units. Thanks!
arrow_forward
The graph below represents the voltage and current of a series RLC circuit.a) Find Rb) Find the resonance frequency if L = 200 µH
arrow_forward
The voltage across a 70 μF�F capacitor is described by the equation vC=(18V)cos(200t)�C=(18V)cos(200�), where t� is in seconds.
Part A
What is the voltage across the capacitor at t� = 0.016 ss ?
Express your answer with the appropriate units.
Part B
What is the capacitive reactance?
Express your answer with the appropriate units.
Part C
What is the peak current?
Express your answer with the appropriate units.
arrow_forward
High-end headphones (such as the likes of Audeze HifiMan) have such high impedance compared to earbuds. If a neodymium driver of a headphones have a diameter of 40mm and a thickness (note that this is a flat cylinder) of 2mm, how much higher is its resistance compared to an earbuds with diameter of 10mm and thickness of 1mm. (ρ= 110x10^-7Ω)
Follow the format:
Given:
Required:
Equation:
Solution:
Answer:
arrow_forward
What is the value of the time constant (in ms) for the circuit below?
arrow_forward
Which one of the phasor diagrams shown below best represents a series LRC circuit driven at resonance? Select one.
arrow_forward
Explain how does temperature effect the operating characteristics of strain gauge? Alsoexplain the requirements of resistance gauge transducer for its optimum working.
arrow_forward
For the circuit shown in FigureP18.30, use Kirchhoff’s rules to obtain equationsfor (a) the upper loop, (b) the lowerloop, and (c) the node on the left side. Ineach case suppress units for clarity and simplify, combining liketerms. (d) Solve the node equation for I36. (e) Using the equationfound in (d), eliminate I36 from the equation found inpart (b). (f) Solve the equations found in part (a) and part (e)
simultaneously for the two unknowns for I18 and I12, respectively.(g) Substitute the answers found in part (f) into the node equationfound in part (d), solving for I36. (h) What is the significanceof the negative answer for I12?
arrow_forward
Equation for LOOP CFEBC and NODE C using KCL and KVL Sign Convention.
arrow_forward
Determine the equivalent resistance at terminal DB
arrow_forward
11. A Wheatstone bridge is used instead of a single resistor strain gage because o Zero balanced o Offer temperature compensation o Better sensitivity and accuracy o All of the above
arrow_forward
Current in a closed RL circuit How many seconds after theswitch in an RL circuit is closed will it take the current i to reachhalf of its steady-state value? Notice that the time depends on Rand L and not on how much voltage is applied
arrow_forward
In the circuit on the side, the capacitor is charged over a resistor. R = 2 kΩ, ε = 10 V and C = 1 µF. Capacitor is not loaded before switch S is closed. According to this:a) Find the time constant of the circuit and the maximum current in the circuit and determine the maximum load amount in the capacitor.b) Write the equations giving the load in the capacitor and the current in the circuit at any time t.
arrow_forward
what will be the equation for loop cfebc and answer for node c using kcl.
arrow_forward
What is the phase constant for the resistor (ϕR)?
arrow_forward
SEE MORE QUESTIONS
Recommended textbooks for you
Related Questions
- For the circuit in fig.11.78 composed of standard values: Determine the time constant. Write the mathematical expression for the current It after the switch is closed Repeat part (b) for VL and VR Determine il and VL at one three- and five-time constants. Sketch the waveforms of iL,VL and VR.arrow_forwardProblem 10: Part (a) Express the maximum voltage ΔVmax, in terms of Imax and Z. ΔVmax = ______ Part (b) Calculate the numerical value of ΔVmax in volts. ΔVmax = ______ Part (c) Calculate the numerical value of the rms current, Irms, in amps. Irms = ______ Part (d) Calculate the numerical value of the rms voltage, ΔVrms in volts. ΔVrms = ______arrow_forwardThe remaining circuit quantities may change instantaneously as required by Kirchhoff's rules. Calculate I1 , I2 , and I3 in amps immediately after the switch ( t = 0 + ), in that order. Finally, calculate Q in uC. (All currents in this and the following two should be positive.)arrow_forward
- What is IC,max(open), the current that flows through the capacitor whose magnitude is maximum during the time when the switch is open? A positive value for the current is defined to be in the direction of the arrow shown. in ampsarrow_forwardExplain the AC operation of electrodynamic instrument in detail.arrow_forwardCan you show me how to work this? I’m thinking I’m getting confused on the units. Thanks!arrow_forward
- The graph below represents the voltage and current of a series RLC circuit.a) Find Rb) Find the resonance frequency if L = 200 µHarrow_forwardThe voltage across a 70 μF�F capacitor is described by the equation vC=(18V)cos(200t)�C=(18V)cos(200�), where t� is in seconds. Part A What is the voltage across the capacitor at t� = 0.016 ss ? Express your answer with the appropriate units. Part B What is the capacitive reactance? Express your answer with the appropriate units. Part C What is the peak current? Express your answer with the appropriate units.arrow_forwardHigh-end headphones (such as the likes of Audeze HifiMan) have such high impedance compared to earbuds. If a neodymium driver of a headphones have a diameter of 40mm and a thickness (note that this is a flat cylinder) of 2mm, how much higher is its resistance compared to an earbuds with diameter of 10mm and thickness of 1mm. (ρ= 110x10^-7Ω) Follow the format: Given: Required: Equation: Solution: Answer:arrow_forward
- What is the value of the time constant (in ms) for the circuit below?arrow_forwardWhich one of the phasor diagrams shown below best represents a series LRC circuit driven at resonance? Select one.arrow_forwardExplain how does temperature effect the operating characteristics of strain gauge? Alsoexplain the requirements of resistance gauge transducer for its optimum working.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you