What is Pulse: Definition and 345 Discussions

In medicine, a pulse represents the tactile arterial palpation of the cardiac cycle (heartbeat) by trained fingertips. The pulse may be palpated in any place that allows an artery to be compressed near the surface of the body, such as at the neck (carotid artery), wrist (radial artery), at the groin (femoral artery), behind the knee (popliteal artery), near the ankle joint (posterior tibial artery), and on foot (dorsalis pedis artery). Pulse (or the count of arterial pulse per minute) is equivalent to measuring the heart rate. The heart rate can also be measured by listening to the heart beat by auscultation, traditionally using a stethoscope and counting it for a minute. The radial pulse is commonly measured using three fingers. This has a reason: the finger closest to the heart is used to occlude the pulse pressure, the middle finger is used get a crude estimate of the blood pressure, and the finger most distal to the heart (usually the ring finger) is used to nullify the effect of the ulnar pulse as the two arteries are connected via the palmar arches (superficial and deep). The study of the pulse is known as sphygmology.

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  1. B

    How fast does the blue pulse travel?

    Homework Statement A beam of red light entering a block of glass (n = 1.52) 10.00 miles thick will emerge 1.75 miles ahead of a blue pulse that entered at the same moment. (a) How long will it take the red light to traverse the glass? µs (b) How fast does the blue pulse travel? m/s...
  2. A

    Average energy density in a pulse of incoherent radiation

    This is from Physics of Atoms and Molecules - Bransden, Joachain - Section 4.1 Homework Statement Show that the average energy density in a pulse of the form (4.13) is \overline{\rho}=2\int_{\Delta\omega}\omega^{2}A_{0}^{2}\left(\omega\right)\mathrm{d}\omega Homework Equations...
  3. B

    Pulse Height Of Pulse Amplifier

    Homework Statement I have attached the question as a photo. It contains two parts. Homework Equations The Attempt at a Solution For part A, is it simply Q=CV where C is given and Q is the elementary charge times 10^6? For B, I am not quite sure where to begin. Any...
  4. M

    Calculating Pulse Delay Time.

    Homework Statement Electrical pulses travel at about half of light speed through coax cables. Determine the pulse delay time for a cable with a length of 20 feet. Homework Equations The Attempt at a Solution I don't think this question is very hard, but I can't find any...
  5. B

    Travelling Pulse on a String

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  6. T

    Can Salome handle pulse jet physics for CFD simulation?

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  7. N

    Find Fourier Transform of Rectangular Pulse w(t)

    Homework Statement I have a rectangular train wave pulse, w(t). I needed to find the Fourier transform. My work can done can be seen in the attachment. Homework Equations My question is, is there a further way to simplify my solution. The Attempt at a Solution See attachment.
  8. A

    Pulse Width Modulation Explained - Relevant Links Included

    Actually i m new to electrical sciences, can anyone please explain me the working principle of a PWM?? and its applications , please provide any relevant links concerning it. Thanks in advance
  9. R

    How many wavelengths are there now in one pulse?

    Homework Statement A certain type of laser emits light that has a frequency of 5.1* 10^14 Hz. The light, however, occurs as a series of short pulses, each lasting for a time of 2.6* 10^-11 s. (a) How many wavelengths are there in one pulse? (b) The light enters a pool of water. The frequency...
  10. B

    Modelling a short square-wave pulse with Telegrapher's Equation

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  11. S

    Plotting Transverse Wave Pulse: f(x,t) at t=0 & t=2s

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  12. S

    Question on Mode locked laser pulse train

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  13. H

    Range of wavelengths from a laser pulse?

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  14. I

    How can i pulse a DC current at a rate of Ghz

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  15. P

    What Does 0.1 Expected Photon Per Pulse Mean in Quantum Cryptography?

    Maybe a stupid question, but anyway. The paper "Experimental Quantum Cryptography" by C. Bennettet al. discusses laser pulses of 0.1 expected photon per pulse. What does that mean physically? Is it that 90% of laser pulses are not pulses at all, containing no photons and thereby no energy? Or...
  16. A

    Generate voltage pulse using pc?

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  17. C

    Optics fibre dispersion, pulse propagation

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  18. L

    Wavelengths of a laser pulse and inductance in tuning of an FM radio

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  19. T

    Pulse Width Modulation (MOSFET Question)

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  20. K

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  21. R

    What is the acoustic power of each pulse?

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  22. A

    Units of Conversion (Pulse)

    Time standards are now based on atomic clocks. A promising second standard is based on pulsars, which are rotating neutron stars (highly compact stars consisting only of neutrons). Some rotate at a rate that is highly stable, sending out a radio beacon that sweeps briefly across Earth once with...
  23. V

    Down-scaled nuclear pulse propulsion

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  24. T

    Designing a 555-Based Monostable for 3.3s Pulse

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  25. S

    The spectrum of a double pulse

    Hi everyone, I was working recently with a Michelson interferometer and measured the spectrum of the two pulses and see how the fringe spacing of the spectrum change as I change the position of one of the two mirrors in the interferometer, that is the time interval between the two pulses. I...
  26. R

    What is the Velocity of a Wave Pulse Described by y(x,t)=De^-(Bx-Ct)^2?

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  27. Phrak

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  28. F

    NDSolve wave pulse propogation

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  29. A

    Rectangular Pulse on a Transmission Line

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  30. D

    MIDI drum pressure to pulse width

    Dear All, I am making a MIDI Drum project. I want to convert the pressure sensed by piezo into pulse width with presetable setting to shift the offset level above which the output pulse will be generated. If you have any other idea to convert pressure to pulse width kindly let me know...
  31. B

    How to tune pulse width of excimer laser?

    Hi, can anyone explain how to tune the pulse width of excimer laser? Thanks Baris
  32. Spinnor

    Pulse of neutrinos, E m, hits plasma->charge seperation?

    Pulse of neutrinos, E>>m, hits plasma-->charge seperation? When a large pulse of neutrinos, each with an energy much greater than the electron rest mass energy, hits some plasma does this give rise to charge separation for the plasma? Could one make a simple argument why this is true or false...
  33. M

    Analyzing a Pulse: Averaging Spectra & Data Window Criteria

    Is this method good for analyzing a pulse? Why is the averaging of the spectra good for noise cleaning? What's the criteria for defining how much windows in a set of data one should take? Anyone who clarifies this has a big thanks from me.
  34. P

    E-field of a laser pulse and Intensity

    Hi, What is the equation for a E field of a single pulse of a laser? If that laser is shined onto say a grating spectroscope (square law detector), how can I go about deriving an expression for Intensity as a function of frequency at the output of the spectroscope? I know that the square...
  35. P

    Super continuum pulse compression

    I have just started to work in a ultrafast spectroscopy lab. My topic that i will be starting on next week is supercontinuum pulse compression. I just graduated with my BS Physics and have only some experience with ultrafast optics. I know the general theory of how these things work and need a...
  36. T

    What happens to a laser pulse that is beamed through a gravity well?

    I believe that the path of the photons will bend towards the center of mass, but I wonder what happens to the wavelength and the pulse shape while the photons are in the gravity well. The photons don't undergo any real acceleration, since they are in free fall, so their wavelengths should...
  37. V

    Unleashing 1.8MJ in Just 1ns: The NIF's Power Per Pulse

    Homework Statement The NIF will use extremely powerful lasers to attempt to implode a D-T target and thus initiate nuclear fusion. One pulse of the lasers will only last for 1 nanosecond, but the total energy is expected to hit 1.8 megajoules. The wavelength is in the near ultraviolet, 350 nm...
  38. M

    Pulse Through Cable: Solving Part A and B

    Hi, this is the question: For part a) I did V=(L/C)-1/2=2.5x108 m/s. And then I said T=x/v where x=10m, so T=4x10-8s. For part b) V++V-=VL...since it's the first wave I suppose there wouldn't be a reflecting wave yet, so V-=0. I have an equation that says V+=[VL/2](1+R0/RL)...since...
  39. Q

    What is the difference between pulse response and impulse response?

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  40. E

    Speed of light pulse if you have a velocity of c

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  41. O

    VFD - 36 Pulse Unit Advantages

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  42. Q

    Does a light pulse get amplified when it goes to a less dense medium?

    Since a string pulse get amplified when it enters a less dense medium such as from the thick heavy rope to a lighter string, why does not light do the same?
  43. M

    Does Universe Pulse? Theory or Naive Guess?

    Is that an official theory or just a light/naive guess (maybe mine)that, if after big bang everything expands, and we can be pretty sure every galactic center is a massive black hole -than galactics are"joining forces" to make it all(universe) back to the point the big bang happens again(and...
  44. V

    Spatio-temporal shape and spectral distribution of pulse

    Hi, everyone. Can someone help me to understand pulse? What is the meaning of temporal shape? is it means the intensity distribution of the pulse is following the shape? What is the relationship between temporal shape and spectral mode distribution? Is that the Fourier transform...
  45. A

    Pulse Jet Propeller Thrust Calculation

    Hello everyone! I recently visited the Air Force museum in Ohio and saw their Pulsejet Helicopter. It was intriguing how they attached a pulsejet to the end of each propeller tip. Since then, I’ve been wondering if two pulsejets could be used on a general aviation propeller. I’d like to...
  46. S

    Benefits of Pulsing an IR Source for Gas Detection Systems

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  47. T

    Lorentz contraction of a light pulse

    Suppose the earth, moon, and an extraterrestial observer(ET) are at the corner of an equilateral triangle. The Earth observer points a laser at the moon and emits a powerful laser pulse for exactly .01 seconds. The 1,860 mile long pulse travels to the moon in about 1.3 seconds. The ET knows that...
  48. B

    Solved: Pulse Wave Problem - Speed of the Crest in m/s

    Homework Statement A string of length l = 5 m weighs M = 10 kg . A pulse wave is traveling along the string. What is the speed v of the crest of the pulse, in the uint of m/s , if the tension of the string F is 200 N ? Homework Equations v= sqrt F/u u= m/L HELP: We can...
  49. N

    Electron cloud from uv pulse aimed at negative plate of a capacitor

    Homework Statement A very short pulse UV laser is used to liberate a number of electrons from the negative plate in the arrangement in (i) above. The electrons drift towards the positive plate under the influence of the electric field over a time scale much longer than the laser pulse...
  50. S

    Energy density expression of a Gaussian pulse

    Hi, Energy density of the ith annular section of a Gaussian pulse is written as F(r_i, r_i+1)=2*totalEnergy/[(r_i+1^2-r_i^2)*w^2]*integral(r*exp(-r^2/w^2),from r_i to r_i+1) where r spans from r=0 to r=r_n (theoretically infinity) in n steps, w is the waist size of the beam. This...
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