In the lab, the open-circuit voltage measured across an
unknown circuit's terminals equals
.
When a 1Ω resistor is place across the terminals, avoltage of
appears.
What is the Thévenin equivalent circuit?
What voltage will appear if we place a 1F capacitor
across the terminals?
Mystery circuit
We want to determine as much as we can about the circuit lurking in the impenetrable box shown in
[link] .
A voltage source
V
has been attached to the left-hand terminals, leaving the right terminals for tests and measurements.
Sammy measures
V when a 1 Ω resistor is attached to the terminals.
Samantha says he is wrong.Who is correct and why?
When nothing is attached to the right-hand terminals, a voltage of
V is measured.
What circuit could produce this output?
When a current source is attached so that
amp, the voltage
is now 3 V.
What resistor circuit would be consistent with this and the previous part?
More circuit detective work
The left terminal pair of a two
terminal-pair circuit is attached to a testingcircuit. The test source
equals
(
[link] ).
We make the following measurements.
With nothing attached to the terminals on the
right, the voltage
equals
.
When a wire is placed across the terminals on
the right, the current
was
.
What is the impedance “seen” from the terminals
on the right?
Find the voltage
if a current source is attached to the
terminals on the right so that
.
Linear, time-invariant systems
For a system to be completely characterized by atransfer function, it needs not only be linear, but also
to be time-invariant. A system is said to betime-invariant if delaying the input delays the output
by the same amount. Mathematically, if
,
meaning
is the output of a system
when
is the input,
is the time-invariant if
for all delays
and all inputs
.
Note that both linear and nonlinear systems have thisproperty. For example, a system that squares its input
is time-invariant.
Show that if a circuit has fixed circuit elements
(their values don't change over time), itsinput-output relationship is time-invariant.
Hint : Consider the differential
equation that describes a circuit's input-outputrelationship. What is its general form? Examine the
derivative(s) of delayed signals.
Show that impedances cannot characterize
time-varying circuit elements (R, L, and C).Consequently, show that linear, time-varying systems
do not have a transfer function.
Determine the linearity and time-invariance of the
following. Find the transfer function of the linear,time-invariant (LTI) one(s).
diode
Long and sleepless nights
Sammy went to lab after a long, sleepless night, and
constructed the circuit shown in
[link] .
He cannot remember what the circuit, represented by theimpedance
, was. Clearly,
this forgotten circuit is important as the output is thecurrent passing through it.
What is the Thévenin equivalent circuit seen by
the impedance?
In searching his notes, Sammy finds that the circuitis to realize the transfer function
Find the impedance
as well as values for the other circuit elements.
Questions & Answers
A golfer on a fairway is 70 m away from the green, which sits below the level of the fairway by 20 m. If the golfer hits the ball at an angle of 40° with an initial speed of 20 m/s, how close to the green does she come?
A mouse of mass 200 g falls 100 m down a vertical mine shaft and lands at the bottom with a speed of 8.0 m/s. During its fall, how much work is done on the mouse by air resistance
Chemistry is a branch of science that deals with the study of matter,it composition,it structure and the changes it undergoes
Adjei
please, I'm a physics student and I need help in physics
Adjanou
chemistry could also be understood like the sexual attraction/repulsion of the male and female elements. the reaction varies depending on the energy differences of each given gender. + masculine -female.
Pedro
A ball is thrown straight up.it passes a 2.0m high window 7.50 m off the ground on it path up and takes 1.30 s to go past the window.what was the ball initial velocity
2. A sled plus passenger with total mass 50 kg is pulled 20 m across the snow (0.20) at constant velocity by a force directed 25° above the horizontal. Calculate (a) the work of the applied force, (b) the work of friction, and (c) the total work.
you have been hired as an espert witness in a court case involving an automobile accident. the accident involved car A of mass 1500kg which crashed into stationary car B of mass 1100kg. the driver of car A applied his brakes 15 m before he skidded and crashed into car B. after the collision, car A s
can someone explain to me, an ignorant high school student, why the trend of the graph doesn't follow the fact that the higher frequency a sound wave is, the more power it is, hence, making me think the phons output would follow this general trend?
Nevermind i just realied that the graph is the phons output for a person with normal hearing and not just the phons output of the sound waves power, I should read the entire thing next time
Joseph
Follow up question, does anyone know where I can find a graph that accuretly depicts the actual relative "power" output of sound over its frequency instead of just humans hearing
Joseph
"Generation of electrical energy from sound energy | IEEE Conference Publication | IEEE Xplore" ***ieeexplore.ieee.org/document/7150687?reload=true
A string is 3.00 m long with a mass of 5.00 g. The string is held taut with a tension of 500.00 N applied to the string. A pulse is sent down the string. How long does it take the pulse to travel the 3.00 m of the string?