Measuring Definition and 962 Threads

Hello everybody. I am new here, and also new to quantum mechanics. This is the question to which I can't answer neither in mathematical nor physical way. a,b → observables (like position and momentum) A,B → corresponding operators. "It is possible for particles to be in a state of...

Using a heat source to increase the temperature of an agricultural commodity like corn, could a thermal camera detect temperature differentials over time as the commodity cools, versus localized surface contaminants such as mold or fungus? I'm thinking yes in theory but the differences might be...

Imagine two parallel conducting plates set at a distance of several meters. If one charges the two plates simultaneously then one would expect a small delay before they started repelling each other due to the time it takes changes in the static field to propagate from one plate to the other...

Good day ! I am trying to read a temperature on a heated cylindrical metal (steel) bar (about 15 mm in diameter) using a pyrometer. However I cannot measure the temperature on this bar. The bar has a rather dim shine on it and I think it affects the reading. Also, maybe because it has a small...

I need to measure a magnetic field of Frequency of around 130KHz in all 3 X,Y,Z axis. I have a plan to make 3 coils perpendicular to each other and measure voltages from each coil in Oscilloscope channel. As per Faraday's law of induction. I could measure (dB/dt) as follows. V = - N A...

Homework Statement The series circuit is connected as follows: A 12V Battery -> 8ohm resistor -> 7V Battery -> 4ohm Resistor -> Earth. The problem states that if a voltmeter was connected from a point between the 12V battery & the 8ohm Resistor and connected to a point above the Earth then...

Does any uncertainty when measuring time? Can we measure time definitely(hundred percent correct)

Homework Statement At t=0 a police officer is located at (0,R) on a circular platform whose radius is R and which rotates around the z axis with constant angular velocity ω. The officer's velocity at that point in time is (ωR ,0). At that time, a bird leaves the center of the platform along the...

Hi guys, For a science experiment I've got to measure the power consumption of my circuit of a 100W incandescent light bulb connected to the mains AC, with a dimmer switch to vary its brightness. I was planning on just using one of those plug-in energy monitors with a digital display but...

Homework Statement Given the following hamiltonian and the observable \widehat{B} find the possible energy levels (a is a real constant). If the state is in it's fundamental state what's the probability of measuring b_{1}, b_{2} and b_{3}? Homework Equations The Attempt at a...

First of all, excuse me if this question is too basic: I feel like it shouldn't be a struggle to understand, but the fact is it is. We put up an antenna to play with radio a little, and someone we were working with showed us that there's a reading on the voltmeter without any of the equipment...

Got the following from a friend who teaches HS physics... Measuring the speed of light with chocolate and a microwave oven http://morningcoffeephysics.com/measuring-the-speed-of-light-with-chocolate-and-a-microwave-oven/

Homework Statement So say I have a 1 qubit normalised state |ψ> = 1/√N(c1|z+> - c2|z->) and I make the measurement Sx and the measurement yields +hbar/2 as |x+> is a superposition of both z+ & z- basis eigenstates does the collapsed state end up the same as the original state? Or would I need...

I know about the Michaelson-Morley expt. trying to measure the speed of light, once in the direction of motion of the Earth and then perpendicular to it. But the source of light was a torch (or similar) which is (obviously) on earth. I have somewhere read that it was also done with the source...

Hi Folks: I'm pondering teaching torque and having students build mobiles as part of that. I started wondering if I could have them derive a torque equation. That started me wondering-if they were placing weights along different lengths of straws or skewers or something, could they weigh...

Homework Statement Hey guys, so here's the question: The energy eigenstates of the hydrogen atom \psi_{n,l,m} are orthonormal and labeled by three quantum numbers: the principle quantum number n and the orbital angular momentum eigenvalues l and m. Consider the state of a hydrogen atom at t=0...

I have to measure the size of a cavity of a animal body(s). What is more important I need to measure it on several bodies and compare the results. The cavity is small and contains liquid. That liquid can be extracted and that sets the volume of cavity to 0. It's important to note that the...

Homework Statement Hi, We're doing an experiment of measuring the thickness of a hair using a laser. So we took a hair, and a laser, and shot it through the hair, to receive the following pattern on the wall. The image of what we received (after red filter applied) on the wall is...

Homework Statement What are the possible results of the measurement of the sum of the x and z components of the spin angular momentum of a spin-1/2 particle? Sx = Spin angular momentum operator x Sz = Spin angular momentum operator x Homework Equations The Attempt at a...

Homework Statement Consider an electron incident on a screen with a narrow slot of width 2d. Assume that the electron is moving with velocity v in the direction perpendicular to the screen and that its wavefunction is uniformly spread over the slit and its vicinity, as shown. After going...

Hello, i'm doing my prep for my lab experiment tomorrow and have a few questions about the experiment. The schematic is attached. My lab script says the following; 2 questions. It says the precise rate of flow of water through the heat exchanger is unnecessary to know. Is this...

Let's say we have 200 electrons. The first batch of 100 of those electrons are prepared in a way that 50% are UP in the x-axis while 50% are DOWN in the x direction. The order is unknown. The second batch of 100 electrons are prepared in the same manner but in the y axis. Bob picks one...

In class, we came up with an equation, a=gtanθ, to calculate the acceleration of a car using a hanging pendulum in Earth's frame of reference (θ being the angle that the pendulum makes with the vertical when the car accelerates). So far, I know that that the pendulum moves in the opposite...

According to QM, given two entangled electrons A and B, if you measure the y-axis spin on A to be up, then you know electron B's y-axis spin is down. Also according to QM, if i understood it properly, you cannot then go on to measure the x-axis spin on B, because then you would know both y...

Hello all, thanks for reading. I'm in the process of designing a machine that will move a hall effect sensor in 3 dimensions through a magnetic field and record readings. Before I started the design however, I wanted to see if there would be huge problems in how I envision this machine...

Hello, I am looking for a way to measure the dosage of a powder (made of metallic particles (ferromagnetic) that are 6 microns large) in a liquid solution that is kerozene. When mixed with the liquid a suspension is obtained that takes about one hour for the powder to settle down. Once...

σx|x>=+|x> σx|-x>=-|-x> These equations also follows for σy and σz corresponds states |y> and |z>. if we measure along axis X then X state vector let it go which means up spin and opposite not go through which means down spin. and also same for y and z axis. But, σx|u>=|d> σx|d>=|u>...

From what I understand, the speed of any object in the universe can only be measured relative to another object in the universe. . . . If this is the case then how can we say time slows down for an object traveling at super high speed. Who is to say which object is moving at super high speed...

I have an instrument whose spec. sheet mentions Accuracy as 2% of FSD. The scale runs from 0 to 1000 Litres per hour. Does this mean if I check the instrument versus a gold standard calibrating instrument at a flow of 500 Litres per hour (which is our typical flow) the absolute error can be...

Think for example a phone or any devices that shows the amount of battery power is left. It shows it as a graphic where you can deem whether it's full, 3/4 full, 1/2 full, 1/4 etc... or shows the actual percentage. What is that measure really showing you? Voltage? Amp hours left (which is the...

Consider an observer equipped with a good ruler and a rod. This observer measures the length of the rod and finds it 30 cm. Now this observer with his ruler and rod rides a spaceship and moves with a high speed. He then tries to measure the length of the rod using his ruler. According the SR...

I have been trying to do an experiment measuring Plank's constant using LED's of different colors. The result I get is out by a factor of nearly two. I.e. I got about 3.7 x 10^-34 Js . I am not sure what I am doing wrong. Using a red Led for example, which has a maximum wavelength of...

Only but few may disagree that the inverse squared law affects speed. For example, not only lengths of far away vehicles shorten, (with increase in distances from obsevation) the moving vehicles generally seem to have "slowed" down; the direction either from right to left or vise versa. Please...

I am relatively new to particle physics, and I seem to have reached confusion already. I do not seem to comprehend how you could measure the momentum of a charged particle just by exerting force and a magnetic field on it. The formula F = Bqv is mentioned when I hear of this, which does not...

Hello: I've three circles as seen in the image. Source: http://www.picpaste.com/Quantify-PwdfQxLB.png Within the innermost circle is a point. I'd like to determine the likelihood, or probability, that this point belongs to the innermost circle, the middle-circle, and outermost...

Problem: 1. The pressure of a gas cell is measured with a mercurcy manometer. The mercury is 32.6 cm higher in the outside arm than in the arm connected to the gas cell. Calculate the gas pressure. Relevant equations/given data 2. p(Pressure at depth h) = p(Pressure of atmosphere) +...

where is end of universe and how can measure it?

Hi, I'm wondering if there's any possible way to do voltage gating to a sample while observing it with a microscope, in order to measure its optical properties while changing its electrical parameters. Thanks

can anyone explain why is that noted?Most of them says that it denotes the error.why there should be an error in the instrument.Can't we make an instrument free of error?confused.

Hey guys, I am working on a project where I am using two photo-transistors to detect the speed of a projectile. I am trying to measure the speed of a paintball but I am getting mixed results. When a slow moving object passes through the sensors the correct speed is displayed but extremely fast...

Hi, I am in the process of trying to develop an air transformer but encountering unusual behaviour which I hope can be explained with some fundamental theory I don't yet know. My set up is as follows; - Two identical wound 13.3uH inductors designed to resonate at 4.364MHz. They are 10...

Hey all, So I took apart an old computer monitor to try and harvest some of the hardware inside so I don't have to buy all that stuff for my hobbying, and I was wondering if it is possible to measure the specs on the transistors inside without having to put them into a circuit and see how...

Let me preface this by saying I know very little about relativity. Last night a friend and I were discussing a particular scenario that will probably arise when humans begin to be capable of interstellar travel. Say you take off from Earth and accelerate to some velocity and then coast until you...

As stated in the title, I am trying to send an ultrasonic pressure wave through a medium using a transducer. However, I am having trouble finding equipment or some type of method that measures within the 100 ns of the pressure applied. Digital Force Gauges and Impact Force Measurement systems...

I am trying to devise a way to test the electrical conductivity/resistivity of the atmosphere through rising altitudes. The platform for the experiment is a NASA weather balloon with the allowance of a 1 kg payload. I have started by creating a sort of leaky capacitor design which involves the...

Hi, I want to run an experiment to try and experimentally determine the efficiency (as in what percent of energy is converted to light) of bioluminescent bacteria (V. Fischeri), and compare it to the efficiency of a "traditional" light source, like an LED or an incandescent. I know how I...

well,i have heard this in many threads. That we can only measure the speed of light by noting down when light completes its full round trip. Now why cannot we measure speed of light by considering the half-way trip?

Dear All My water tank fixed on roof top 5M from the ground Height of tank 1m width of tank .75m ( Cylinder type water tank ) if water out from the tank by .5 inch hose how can I measure the pressure at 1m height from the ground Please advice Thanks in advance

1. An oscilloscope is used to measure the voltage across two components using Channel A and Channel B. Deduce the RMS voltage of the signal measured by Channel A I just want to know what they mean by "deduce the RMS voltage" Do i need to calculate the Vrms?

I am looking at EMI Shielding effectiveness testing and I would like to measure how a material is shielding Electromagnetic waves, qualitatively. Is there a way to measure how a material is shielding qualitatively and quantitatively (in dB)?