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Circuits filter!

A unit-amplitude pulse with duration of one second serves as the input to an RC-circuit having transfer function H f 2 f 4 2 f

  1. How would you categorize this transfer function: lowpass, highpass, bandpass, other?
  2. Find a circuit that corresponds to this transfer function.
  3. Find an expression for the filter's output.

Reverberation

Reverberation corresponds to adding to a signal its delayed version.

  1. Assuming τ represents the delay, what is the input-output relation for a reverberation system? Is the systemlinear and time-invariant? If so, find the transfer function; if not, what linearity or time-invariancecriterion does reverberation violate.
  2. A music group known as the ROwls is having trouble selling its recordings. The record company'sengineer gets the idea of applying different delay to the low and high frequencies and adding theresult to create a new musical effect. Thus, the ROwls' audio would be separated into two parts (oneless than the frequency f 0 , the other greater than f 0 ), these would be delayed by τ l and τ h respectively, and the resulting signals added. Drawa block diagram for this new audio processing system, showing its various components.
  3. How does the magnitude of the system's transfer function depend on the two delays?

Echoes in telephone systems

A frequently encountered problem in telephones is echo. Here, because of acoustic coupling between the ear pieceand microphone in the handset, what you hear is also sent to the person talking. That person thus not onlyhears you, but also hears her own speech delayed (because of propagation delay over the telephonenetwork) and attenuated (the acoustic coupling gain is less than one). Furthermore, the same problem appliesto you as well: The acoustic coupling occurs in her handset as well as yours.

  1. Develop a block diagram that describes this situation.
  2. Find the transfer function between your voice and what the listener hears.
  3. Each telephone contains a system for reducing echoes using electrical means. What simple system couldnull the echoes?

Effective drug delivery

In most patients, it takes time for the concentration of an administered drug to achieve a constant level in the blood stream. Typically, if the drug concentration in the patient's intravenous line is C d u t , the concentration in the patient's blood stream is C p 1 a t u t .

  1. Assuming the relationship between drug concentration in the patient's drug and the delivered concentration can be described as a linear, time-invariant system, what is the transfer function?
  2. Sometimes, the drug delivery system goes awry and delivers drugs with little control. What would the patient's drug concentration be if the delivered concentration were a ramp?More precisely, if it were C d t u t ?
  3. A clever doctor wants to have the flexibility to slow down or speed up the patient's drug concentration. In other words, the concentration is to be C p 1 b t u t , with b bigger or smaller than a . How should the delivered drug concentration signal be changed to achieve this concentration profile?

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?
Aislinn Reply
cm
tijani
what is titration
John Reply
what is physics
Siyaka Reply
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
Jude Reply
Can you compute that for me. Ty
Jude
what is the dimension formula of energy?
David Reply
what is viscosity?
David
what is inorganic
emma Reply
what is chemistry
Youesf Reply
what is inorganic
emma
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
Krampah Reply
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.
Sahid Reply
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
Samuel Reply
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?
Joseph Reply
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
Ryan
what's motion
Maurice Reply
what are the types of wave
Maurice
answer
Magreth
progressive wave
Magreth
hello friend how are you
Muhammad Reply
fine, how about you?
Mohammed
hi
Mujahid
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?
yasuo Reply
Who can show me the full solution in this problem?
Reofrir Reply
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Source:  OpenStax, Pdf generation problem modules. OpenStax CNX. Sep 23, 2008 Download for free at http://cnx.org/content/col10514/1.4
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