Measuring Definition and 962 Threads

Is anyone expermently measured two way speed of light from moving source using time of flight?

Homework Statement [/B] Find reading of ohmmeter. Homework Equations V=IRThe Attempt at a Solution I am a beginner of this topic and I think it is simple as ohmmeter directly measure the resistance of the resistor which is 2k ohm while the correct answer is 1.67k ohm. I have no idea how to get...

Romer measured speed of light using moon's of Jupiter but he got value with a error of 26%. Is anyone did same experiment in modern era? And what value they got?

Homework Statement Its a general question asking which method of measuring resistance (a 5 ohm resistor in a simple circuit) has greatest precision. The first method I varied voltage from about 5V to 10V, then measured the current each time, then averaged that current and calculated resistance...

<Moderator's note: Moved from the welcome forum. General question on the measurement of angles and thus no homework.> So we have a physics lab and here's the diagram. I do know how to calculate all but i got negative angle. Does that mean that that angle is reference to the negative x quadrant...

Is measuring pressure for a compressible fluid system angle dependent?For a compressible fluid, Bernoulli's Law gives us a relation between two points along a closed system. More specifically it gives us the relation between two cross sections belonging to two distinct points in the closed...

I’m understanding that if you prepare a QM system, say 2 electrons in a singlet state and do nothing to the system then when the measurement is made the 2 electrons will still be in the singlet state. If that is true, then I don’t see anything surprising that if Bob measures his electron as up...

Hi, I'm wondering if it is possible to measure radii of stars using general relativity, given its explanation of gravity as curvature of space. Thank you

https://aapt.scitation.org/doi/10.1119/1.5064562 The availability of inexpensive Doppler radar has made it practical to accurately measure drag coefficients in undergrad physics labs.ABSTRACT Undergraduate lab design balances several factors: 1) simple experiments connected with learning...

I am performing an experiment where I have built a scale model of a wind turbine, and am measuring the current it can produce with a micro generator. I am using a standard multi meter and the micro generator is DC. I do not know much about the topic, but whenever I start measuring the current...

What could be the method for measuring weight of gas in inflated balloon? Thanks & Regards, Prashant S Akerkar

Hi Everyone, I am working on a project which requires me to determine the torque on the impeller shaft of stirred tank. Currently as I see it, there are 2 viable options: To measure the torque in the shaft using a torque transducer such as this one. This is by far the most accurate means of...

Hello, I would like to ask about the process of measuring the Spin of a Dirac 4-spinor Ψ that is not in the rest frame. Note that even though there is plenty of information about what a Dirac spinor is, what reasoning lead to its discovery and how it can be expressed in terms of particle and...

I was away for a few months and thought I might pose this thought I am working on, on this forum when I return. There was a very help full person who assisted me in the finer explanation of the Lorenz transformation a few months ago, and I really learned a lot about SR and GR. A few weeks ago, I...

Quantumly speaking: Can speed be measured? If so, why? If not why? This is a serious question. Speed involves a distance unit and a time unit. For example .. "ft/sec" .. and it is illogical to divide seconds into feet. Having made this point can speed be quantumly measured and how do you...

I am an amateur scientist interested in all fields of science. What voltage potential is used to measure the EC of water to approximate TDS of filtered tap water?

Recently I read something in NASA Tech Briefs about an instrument that could measure phase differences as small as .001 degree in light. I would like to create an instrument that could do this for every pixel in a picture, even if it was only a few hundred pixels (such as a 20x30 pixel array)...

Special relativity is replete with examples of turning mirrors into clocks. Place two mirrors across from one another, bounce light between them, and measure the time. But as I thought about this, when a photon hits the mirror, it is absorbed by an electron which moves to a higher energy...

Drive two 15m long optical fibers extended in opposite directions with a 1GHz pulse generator. The recievers at the end of each fiber are now syncronised sources of 1GHz pulses. Connect them to pulse counters, one of which provides a signal whenever a pulse train is present. Connect this...

Hello. How would this be done? Using a step up transformer?

The speed of light from a moving source of light is usually recognized indirectly, based on various explanations of phenomena. The speed of light is fairly simple directly measurable on the basis of autonomous and separate measurements of the frequency and wavelength of the light. Is a similar...

Consider a scattering between two particles a and b that produces two particles c and d: d is stable, while c decays in two other different particles e and f. The first interaction is by strong force (time of interaction ##t_1\sim 10^{-23}s##, which is also the time of generation of c and d)...

Hi this is my first question and love these Forums. I have a Independent research task due next term. My idea was: Seeing the change of wave length of light as it passes through different substances. My question is: How do i measure the wave length? Because I could use a spectrometer but my...

I was solving an exercise from Cohen's textbook, but then I got stuck in this question. "Let ψ(x,y,z) = ψ(r) the normalized wave function of a particle. Express in terms of ψ(r) the probability for: b) a measurement of the component Px of the momentum, to yield a result included between p1...

Hello, I am on the search for papers, books, etc. on how one can measure the viscosity of viscous materials via the speed of sound. I've searched for a while now and haven't been able to find much on this topic. Any help is greatly appreciated.

Suppose we have an ultrasonic transmitter and an ultrasonic receiver, separated by some fixed distance ##d##. Both devices are attached to an oscilloscope. The transmitter generates ultrasonic waves at some frequency ##f## that we can change. The receiver is some piezoelectric that translates...

Watching an old (2012) youtube video (), the narrator says (time 10:38) that if A measures the y-axis spin of an entangled pair and communicates his finding to B, then B "cannot" measure his x-axis spin, because doing so would give him knowledge of the spins along both axes, which uncertainty...

Morning! I was performing some experiments about impulse and conservation of mechanical energy, and for that I was looking to good ways of measuring the velocity of a sphere under the action of a force. In free fall, having the height H it was falling along, I have used the formula v =...

I don't know what's the appropriate title for my question but here it is: What's the reference we consider to measure the speed with respect to when we say that as the speed of a moving object approaches the speed of light the time becomes slower in the frame of this moving object.

Suppose you have an experiment that measures the property of an atom as a whole, maybe you can put it through a double-slit or measure its spin, whatever. Presumably that will collapse the wavefunction that you used to describe the atom in that experiment. Would this entail that in the process...

Homework Statement a) If you were using a hands –on activity to verify your predictions and use measurements to determine the wavelength of the laser being used, describe any safety precautions you would have to take and sources of error that you might encounter. Be sure to explain how you...

For physical experiment I have a project in which I have to measure the speed of sound in the air. 1. If I take an iron tube (inside is air) and a speaker, 2. put the speaker at the beginning of a tube, 3. speaker is connected to frequency generator (with which I can change frequencies)...

In measuring the internal resistance of a power supply, why is a resistor with low resistance used?

Heya, I was wondering what happens when you measure the spin of particles along several different angles on an entangled pair. As far as I understand Bell's theorem, it basically says that if you first measure particle A in some angle, and then measure a particle B at some some angle, you'll...

From our perspective the Universe is expanding faster the further away things get, correct? Given that we are measuring further and further back in time my question is this. If you were at the furthest known point in the Universe looking back at our galaxy and attempting to measure the expansion...

I'm trying to measure high voltages with a DAQ card. Obviously I'm going to have to attenuate the voltage, but I need to make sure that I can measure accurately (within 1%) The code width of the DAQ is Vcw = 20Vpp/2^16 = 305.176uV For this code width to be within 1%, the minimum voltage I...

Morning! My question is this: If we consider a situation of mechanical collision, in the real world we shall observe certain loss of energy into heat or sound. Can we find mathematical equations to measure the amount of sound or heat produced using only mechanical variables, such as mass...

Hello Theoretically any ball that bounces 1.225 metres high is in the air for one second. This is fairly precise, +/-4% time variance is +/- 10 cm height variance, so bouncing to a height of 1.13 metres is 0.96 seconds and to a height of 1.32 is 1.04 seconds. The theory is at least dependent...

Homework Statement Homework Equations For question 14 PMMC measures average value MI measures RMS value The Attempt at a Solution I think PMMC should give 0 V But book answer is B i.e 1 V (where am I wrong?) and MI should give 1.414 V. For this book answer matches my answer.

How is it reliably ascertained that the "particles" 'measured' can be "proven" to have "traversed the experiment" and are not just conveniently (or inconveniently depending on perspective) incident / external? Is this obtained through statistical analysis from a large number of repetitions...

Good morning. I've just completed working through Einstein's work on special and general relativity. Do I understand that, in relativity, a moving object cannot measure its own speed without an external reference to compare to? IE, there is no experiment it can conduct to determine its own...

Hi all, My question is in reference to the following paper: https://arxiv.org/pdf/1202.1783.pdf In equation 3.8, the author computes an order-of-magnitude approximation of probability of measuring negative momentum from the following wavefunction: $$ \Psi_k =\sum_{k=1,2}...

a) dimension the moving-coil movement so that it indicates full deflection at 25 V given Values: Voltage Source: U2Max = 25V; moving-coil movement: IM = 100µA; UM = 270mV Rv = ( U2Max - UM ) / IM = (25V - 270mV) / 100 µA = 247,3kΩ b) the internal resistance is increased by 20 %...

Homework Statement This is a problem from the Cambridge Natural Science Admissions Assesment. A student carries out an experiment to measure the speed of sound. A loudspeaker that emits sound in all directions is placed between two buildings that are 128 m apart as shown. The student and...

Homework Statement Hi! So I stumbled upon this simple "plug n' play" exercise in my Physics textbook. Basically it gives you certain molecules/atoms, and tells you to measure the Electric Charge, and its Mass. Pretty simple, but I hit upon some hickups. Anyway, let's get to it: Find the...

Homework Statement We were given this question on a worksheet last lecture. The question is this: ‘Throw a tennis ball/your pen/some non-dangerous object into the air, straight up (and catch it again), observe its motion. Use your observation to measure the gravitational acceleration due to...

I just started learning about oscilloscopes and I am confused on how to calculate the uncertainty. The uncertainty measurement on the device says '1/2 the smallest division'. I am unsure which 'division' this refers to since there are horizontal scales and vertical scales. In my experiment I...

Hey folks, I built a generator for fun and I would like to find out how much power it is producing when I use it. I have a way of measuring mechanical power in but I am not quite sure on how to measure electrical power out. I'm thinking I could use some LEDs to create a load (or maybe...

Homework Statement I understand that the DC current will not flow through the capacitor once the capacitor gets fully charged. So, after a long time , only AC component of the net current flow through the capacitor. How to show that all of the carying voltage appear across the capacitor...

In the ideal gas law, the symbol n represents the number of moles of gas. My question is how, given a volume of a certain gas, one determines how many moles one has. My understanding is that a mole in this case denotes a quantity of particles. How does one determine how many moles one has...