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A testing circuit

The simple circuit here was given on a test.

When the voltage source is 5 t , the current i t 2 t 2 4 .

  1. What is voltage v out t ?
  2. What is the impedance Z at the frequency of the source?

Black-box circuit

You are given a circuit that has two terminals for attaching circuit elements.

When you attach a voltage source equaling t to the terminals, the current through the source equals 4 t 4 2 4 t . When no source is attached (open-circuited terminals),the voltage across the terminals has the form A 4 t φ .

  1. What will the terminal current be when you replace thesource by a short circuit?
  2. If you were to build a circuit that was identical (from the viewpoint of the terminals) to the givenone, what would your circuit be?
  3. For your circuit, what are A and φ ?

Solving a mystery circuit

Sammy must determine as much as he can about a mystery circuit by attaching elements to the terminal andmeasuring the resulting voltage. When he attaches a 1Ω resistor to the circuit's terminals, he measuresthe voltage across the terminals to be 3 t . When he attaches a 1F capacitor across the terminals,the voltage is now 3 2 t 4 .

  1. What voltage should he measure when he attaches nothing to the mystery circuit?
  2. What voltage should Sammy measure if he doubled the size of the capacitor to 2 F and attached it to thecircuit?

Find the load impedance

The depicted circuit has a transfer function between the output voltage and the source equal to H f -8 2 f 2 -8 2 f 2 4 6 f .

  1. Sketch the magnitude and phase of the transfer function.
  2. At what frequency does the phase equal 2 ?
  3. Find a circuit that corresponds to this loadimpedance. Is your answer unique? If so, show it to be so; if not, give another example.

Analog “hum” rejection

“Hum” refers to corruption from wall socket power that frequently sneaks intocircuits. “Hum” gets its name because it sounds like a persistent humming sound. We want to finda circuit that will remove hum from any signal. A Rice engineer suggests using a simple voltage divider circuit consisting of two series impedances.

  1. The impedance Z 1 is a resistor. The Rice engineer must decide between two circuits for the impedance Z 2 . Which of these will work?
  2. Picking one circuit that works, choose circuit elementvalues that will remove hum.
  3. Sketch the magnitude of the resulting frequency response.

An interesting circuit

  1. For the circuit shown in [link] , find the transfer function.
  2. What is the output voltage when the input has the form i in 5 2000 t ?

A simple circuit

You are given the depicted circuit .

  1. What is the transfer function between the source and the output voltage?
  2. What will the voltage be when the source equals t ?
  3. Many function generators produce a constant offset in addition to a sinusoid. If the source equals 1 t , what is theoutput voltage?

An interesting and useful circuit

The depicted circuit has interesting properties, which are exploited in high-performance oscilloscopes.

The portion of the circuit labeled "Oscilloscope" represents the scope's input impedance. R 2 1 and C 2 30 pF (note the label under the channel 1 input in the lab'soscilloscopes). A probe is a device to attach an oscilloscope to a circuit, and it has theindicated circuit inside it.

  1. Suppose for a moment that the probe is merely a wire and that the oscilloscope is attached to a circuitthat has a resistive Thévenin equivalent impedance. What would be the effect of theoscilloscope's input impedance on measured voltages?
  2. Using the node method, find the transfer function relating the indicated voltage to the source whenthe probe is used.
  3. Plot the magnitude and phase of this transfer function when R 1 9 and C 1 2 pF .
  4. For a particular relationship among the elementvalues, the transfer function is quite simple. Find that relationship and describe what is so specialabout it.
  5. The arrow through C 1 indicates that its value can be varied. Select the value for this capacitor to make the specialrelationship valid. What is the impedance seen by the circuit being measured for this special value?

Questions & Answers

how does Neisseria cause meningitis
Nyibol Reply
what is microbiologist
Muhammad Reply
what is errata
Muhammad
is the branch of biology that deals with the study of microorganisms.
Ntefuni Reply
What is microbiology
Mercy Reply
studies of microbes
Louisiaste
when we takee the specimen which lumbar,spin,
Ziyad Reply
How bacteria create energy to survive?
Muhamad Reply
Bacteria doesn't produce energy they are dependent upon their substrate in case of lack of nutrients they are able to make spores which helps them to sustain in harsh environments
_Adnan
But not all bacteria make spores, l mean Eukaryotic cells have Mitochondria which acts as powerhouse for them, since bacteria don't have it, what is the substitution for it?
Muhamad
they make spores
Louisiaste
what is sporadic nd endemic, epidemic
Aminu Reply
the significance of food webs for disease transmission
Abreham
food webs brings about an infection as an individual depends on number of diseased foods or carriers dully.
Mark
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Esinniobiwa Reply
Assimilatory nitrate reduction is a process that occurs in some microorganisms, such as bacteria and archaea, in which nitrate (NO3-) is reduced to nitrite (NO2-), and then further reduced to ammonia (NH3).
Elkana
This process is called assimilatory nitrate reduction because the nitrogen that is produced is incorporated in the cells of microorganisms where it can be used in the synthesis of amino acids and other nitrogen products
Elkana
Examples of thermophilic organisms
Shu Reply
Give Examples of thermophilic organisms
Shu
advantages of normal Flora to the host
Micheal Reply
Prevent foreign microbes to the host
Abubakar
they provide healthier benefits to their hosts
ayesha
They are friends to host only when Host immune system is strong and become enemies when the host immune system is weakened . very bad relationship!
Mark
what is cell
faisal Reply
cell is the smallest unit of life
Fauziya
cell is the smallest unit of life
Akanni
ok
Innocent
cell is the structural and functional unit of life
Hasan
is the fundamental units of Life
Musa
what are emergency diseases
Micheal Reply
There are nothing like emergency disease but there are some common medical emergency which can occur simultaneously like Bleeding,heart attack,Breathing difficulties,severe pain heart stock.Hope you will get my point .Have a nice day ❣️
_Adnan
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Innocent
I think infection prevention and control is the avoidance of all things we do that gives out break of infections and promotion of health practices that promote life
Lubega
Heyy Lubega hussein where are u from?
_Adnan
en français
Adama
which site have a normal flora
ESTHER Reply
Many sites of the body have it Skin Nasal cavity Oral cavity Gastro intestinal tract
Safaa
skin
Asiina
skin,Oral,Nasal,GIt
Sadik
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Sadik
How can Commensal Bacteria change into pathogen?
Sadik
all
Tesfaye
by fussion
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what are the advantages of normal Flora to the host
Micheal
what are the ways of control and prevention of nosocomial infection in the hospital
Micheal
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Shelly Reply
part of a tissue or an organ being wounded or bruised.
Wilfred
what term is used to name and classify microorganisms?
Micheal Reply
Binomial nomenclature
adeolu
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Source:  OpenStax, Fundamentals of electrical engineering i. OpenStax CNX. Aug 06, 2008 Download for free at http://legacy.cnx.org/content/col10040/1.9
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