Length Definition and 1000 Threads
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Calculate the coherent length of this LED
Answer:- nao113
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- Coherent Led Length
- Replies: 5
- Forum: Introductory Physics Homework Help
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MHB Why do we need "total length" field in ipv4 datagram?
TBH I don't really understand the question that I am asking myself. I was inspired asking this from my textbook "Do you know". Can you make me understand why would not we require total length field? Here's a similar question-...- shivajikobardan
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- Field Length
- Replies: 1
- Forum: Programming and Computer Science
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Comp Sci Total length IP header and 65535 bytes relation-:
So IPV4 header has a topic called "total header length" and it is of 16 bits. That means it can count from 0-65535. Book says it means IP datagram is limited to 65535 bytes. how do we get to idea of 65535 bytes? is it 1 memory location=1 byte idea? It doesn't make any sense to me(I have studied...- shivajikobardan
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- bytes Length Relation
- Replies: 5
- Forum: Engineering and Comp Sci Homework Help
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Length of AD inside a triangle ABC
I get the answer but my working is really long: 1) Find all the length of sides of the triangle 2) Let DB = x, so CD = CB - x 3) Compare the area of triangle ADC and ABD using formula 1/2 . a . b sin θ then find x 4) Find cosine of angle B by using cosine rule on triangle ABC 5) Use cosine rule...- songoku
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- Length Triangle
- Replies: 5
- Forum: Precalculus Mathematics Homework Help
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The length of the line in the MCNP cell card MCNP
Homework Statement:: I go back to the line to finish the previous line in MCNP cell card but I had the error message shown in the photo. Please make a solution to my problem Relevant Equations:: c ********************* BLOCK 1: cartes des cellules **************** 1 2 -1.184 -40 #3 #19 #18...- Asmae SAADI
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- Cell Length Line Mcnp Mcnpx
- Replies: 2
- Forum: Nuclear Engineering
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Stick is broken randomly EDIT TWICE, what is expected length of small side?
Cut the stick twice, at locations ##x## and ##y##. Assume ##y>x##. The lengths of the stick are ##x,y-x,1-y##. Assume ##x < y-x \implies y> 2x## and ##x<1-y \implies y < 1-x##. These two boundaries intersect at ##x = 1/3##. Thus the following integral should yield the expected value for ##x##...- member 428835
- Thread
- Broken Edit Length
- Replies: 29
- Forum: Calculus and Beyond Homework Help
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How do you know if the focal length is positive or negative?
In this problem, it doesn't tell you where is the focal length. So how do you know if it is in front or behind the object?- bluesteels
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- Focal Focal length Geometric optics Length Negative Physic Positive
- Replies: 5
- Forum: Introductory Physics Homework Help
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How can an event which has length and time have L = 0?
I apologize if this is a stupid question I just always thought length involves 2 points to have a length at different locations.- rgtr
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- Length Time
- Replies: 13
- Forum: Introductory Physics Homework Help
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Time falling on slopes of same length
- feynman1
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- Falling Length Time
- Replies: 8
- Forum: Introductory Physics Homework Help
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MHB Formula to find arc radius using arc length, chord length, and/or segment angle
I'm attempting to write some code using the Ruby programming language that will give me the radius of an arc but the only pieces of information I have to work with are the arc length (L), the chord length (C), and the circular segment angle in degrees (A): I'm hoping someone can show me how to...- Alaskan Son
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- Angle Arc Arc length Chord Formula Length Radius
- Replies: 4
- Forum: General Math
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I Length contraction in General Relativity
In GR, a free falling object when viewed by a distant observer appears to be length contracted and slows down as it approaches the event horizon of a black hole. The length contraction piece, however, seems counterintuitive. I would have thought that the leading edge of the object would...- knowwhatyoudontknow
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- Contraction General General relativity Length Length contraction Relativity
- Replies: 64
- Forum: Special and General Relativity
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I Finding focal length of the lens using "u-v" method
I was just checking out this experiment for finding focal length of a lens that I did few years back. the method used was called as the u-v method(https://www.concepts-of-physics.com/pdf/uv-method.pdf), and here in this method, object distance u and image distance v is measured from the sharp... -
B Length, Time, and Velocity -- Which are fundamental quantities?
We think of length and time as the first fundamental quantities and velocity as the first derived quantity but any two determine the third so we would be completely justified in defining velocity as a fundamental quantity and one of length or time as the other, with the remaining being the first...- Keith Koenig
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- Fundamental Length quantities Time Velocity
- Replies: 50
- Forum: Other Physics Topics
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Length of spin vector for spin-½ particle
My answer so far in |S| = √3 /2 *hbar but the question states it must be an angular momentum. Is this an angular momentum or am I missing something? Thanks- ghbeefcake
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- Length Particle Spin Vector
- Replies: 1
- Forum: Advanced Physics Homework Help
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Time dilation and length contraction for a rocket
Hi, It's not a homework but still thought to post it here as advised in the past. A rocket is going to leave Earth's surface and it is decided that a data pulse encoding emission time of pulse will be sent every second from Earth station to the rocket, and the rocket would do the same. The...- PainterGuy
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- Contraction Dilation Length Length contraction Rocket Time Time dilation
- Replies: 12
- Forum: Introductory Physics Homework Help
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I Between a Zeptometer and the Planck length
What exists between approximately 1 X 10 E-21 meters (preon length?) and the Planck Length of 1.6 X 10 E-35 meters?- PEGELLA
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- Length Planck Planck length
- Replies: 2
- Forum: Beyond the Standard Models
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Help identifying a length for this paper edge
Hi PF! Two years ago my lab launched experiments aboard the ISS. The experiment was simple: place two water droplets on a substrate, set camera above the drops, and watch them coalesce. However, the exact size of the drops is unknown (approximately 1 cm radii, though this number is debated)...- member 428835
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- Edge Length Paper
- Replies: 12
- Forum: General Discussion
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Find focal length of electron for a parabolic motion
Here I was going to use ##\int \vec F \cdot d\vec l = \frac{1}{2}mu^2## What I got that is ##l=\frac{mu^2}{2eE}##. Here the question is what is ##l## (I took ##x## while doing the work but here I used ##l## instead of ##x##)? I was assuming that it's ##x## since I am calculating work in the...- Istiak
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- Electron Focal Focal length Length Motion Motion in 2d Parabola
- Replies: 3
- Forum: Introductory Physics Homework Help
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Finding the length of this side of similar figures
Is it possible to find the value of ##x##? I feel like the information is not enough to find it. I have found EF, which is 19.8 cm (if this is helpful) Thanks- songoku
- Thread
- Length
- Replies: 5
- Forum: Precalculus Mathematics Homework Help
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MHB - Length of curve to 4 decimal pl
8.1.1 find the length of the curve to four decimal places $y=xe^{-x},\quad 0 \le x \le 2$ eq from book $L=\int_c^d\sqrt{1+[g'(y)]^2}\, dy$ ok I haven't done this in about 2 years and only did a few then so trying to review rare stuff kinda desmos graph -
B Check my understanding of Time Dilation and Length Contraction
I just started learning about Special Relativity and have come upon the topics of Time dilation and Length contraction. Its a bit abstract for me and I just want to cross ref my knowledge here and see if someone can tell me if I am understanding this correctly. I've attached an excerpt of a...- guyvsdcsniper
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- Contraction Dilation Length Length contraction Time Time dilation
- Replies: 11
- Forum: Special and General Relativity
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B Any plausible explanation for dynamical length contraction?
I am new here, so pardon my ignorance. First of all, I am aware of the impossibility to distinguish experimentally between SR (Special Relativity) and LET (Lorentz Ether Theory). I know there is a PF policy article on LET and the Block Universe. I must admit though that LET is more appealing...- alexandrinushka
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- Contraction Explanation Length Length contraction Relativity Relativity of time Special relativity
- Replies: 83
- Forum: Special and General Relativity
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How to determine the minimum grid length | Numerical Plasma Physics
Summary:: I am learning particle-in-cell (PIC) python 3X code. PIC currently represents one of the most important plasma simulation tools. It is particularly suited to the study of kinetic or non-Maxwellian effects. I am learning particle-in-cell (PIC) python code. PIC currently represents one...- JD_PM
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- Grid Length Minimum Numerical Physics Plasma Plasma physics
- Replies: 7
- Forum: Advanced Physics Homework Help
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B What is a suitable term for relativistic length in STEM education?
Comments please Is there good sobriquet to use for relativistic length ? Just a thought to aid the struggling college frosh STEM students- hutchphd
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- Length Mass Relativistic Relativistic mass
- Replies: 6
- Forum: Special and General Relativity
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Comp Sci Complexity for generating strings of length k from CNF grammar
Here's the following code I've written for generating strings of length k given a CNF grammar ( Chomsky Normal Form grammar ) ( The code is a recursive variant of the CYK algorithm ). The algorithm is recursive and uses memoization. def generate_language(rule_dict, start_var, k): mem =...- CGandC
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- Complexity Language Length Recursion Strings
- Replies: 3
- Forum: Engineering and Comp Sci Homework Help
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I Because of length contraction, does absolute position exist?
I know that I have heard that GR proves that there is no absolute time, so does this go for location too? If so, could it be said that particles have a superposition in position/location the same way that particles do in QM?- student34
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- Absolute Contraction Length Length contraction Position
- Replies: 88
- Forum: Special and General Relativity
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I Judge Original Time & Length Special Relativity
How to Judge original time and original length of special relativity- Barry Z
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- Length Relativity Special relativity Time
- Replies: 8
- Forum: Special and General Relativity
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Guitar string tension: effect of total length - continued
This wiki page offers an incomplete equation for calculating tension over a length of string. Can you please help complete the equation? https://en.wikipedia.org/wiki/String_bending It is referenced here in this thread post #23...- mythbuster
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- Guitar Length String Tension
- Replies: 5
- Forum: Mechanical Engineering
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I Linear Accelerator Length Contraction
I am trying to understand the effect of relativistic length contraction on the electron bunches in a linear accelerator. Figure B is for nonrelativistic speeds, successive cylinder lengths are progressively longer. However, wikipedia says "At speeds near the speed of light, the incremental...- Orthoceras
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- Accelerator Contraction Length Length contraction Linear Linear accelerator
- Replies: 1
- Forum: Special and General Relativity
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B The Paradox of Relativity Length Contraction
A rigid rod with length ## l_0## slides on a smooth and flat tabletop along the length at speed of ## ~\frac {\sqrt{3}}{2}c~ ##, there is a hole of width ##~l_0~##on the table. The observer who is stationary relative to the desktop thinks that the length of the rigid rod ##~ l=l_o...- alan123hk
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- Contraction Length Length contraction Paradox Relativity
- Replies: 166
- Forum: Special and General Relativity
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MHB B20.<= to the length of the dividend
Do the division using the c-strips to make a train of as many of the divisor as possible such that the length of the train you make is less than or equal to the length of the dividend, and if you were to add one more of the divisor to the train, it would be longer than the dividend. If the train...- karush
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- Length
- Replies: 1
- Forum: General Math
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Does wire length difference create phase shift?
When wiring a 240 volt AC circuit, I've always assumed that it's important for L1 and L2 wires to be the exact same length, in order to avoid introducing a phase shift that would reduce peak voltage. Length differences can accumulate when the wires enter a panel and need to go slightly...- yahastu
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- Difference Length Phase Phase shift Shift Wire
- Replies: 5
- Forum: Electrical Engineering
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Uncertainty of pendulum period and pendulum length
I'm doing a lab report where I manually measure the time taken for a bifilar pendulum to do 10 oscillations. Is there a rule or a method that I should follow to calculate its uncertainty? Or is the uncertainty just an estimation of human reaction time and judgment? I also need to know the...- dobbygenius
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- Length Pendulum Period Uncertainty
- Replies: 7
- Forum: Introductory Physics Homework Help
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Need help with this unequal length bifilar pendulum
[Mentor Note -- Three threads on the same problem have been merged into this one] Hi, I'm doing a lab report on the relationship between the period of oscillations in an unequal length bifilar pendulum. The set up is like below Can anyone help me derive a formula for the period of oscillations...- dobbygenius
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- Bifilar Length Mechanics Pendulum
- Replies: 21
- Forum: Introductory Physics Homework Help
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I Shorten the lens distance while having same focal length?
Hello Everybody, I'm David from Spain, and happy to be here. We have a LED that needs a FL50mm collimator which is focused to infinite, because we want parallel rays. So the lens is at a distance 50mm (approx) from the led. However, 50mm is too much distance for our design, so the question is...- Horizont22
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- Focal Focal length Led Length Lens Optic
- Replies: 13
- Forum: Optics
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Engineering Finding arc length of a pipe between two tanks
I can't seem to find the arclength between A and B. I tried using L = integral (0.6 to 0.4) of sqrt (1+ (dz/dx)^2) to no avail. Would it be roughly similar to 400 km (the length from A to B) since the change in elevation could be considered negligible? Furthermore, how might I go about...- knotted_pine
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- Arc Arc length Fluid mechanics Length Pipe Statics
- Replies: 1
- Forum: Engineering and Comp Sci Homework Help
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What causes variations in delay in coax cable of the same length?
Hey all, I was doing some tests in lab when I noticed that between two 4.5m RG174 SMA cables, there was a 1ns difference in delay at 4MHz between the two cables. To clarify, theory says 4.5m of RG174 (66% velocity factor) at 4 MHz should have a delay of 22.7ns. I measured one cable at 22ns and...- Twigg
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- Cable Delay Length
- Replies: 22
- Forum: Electrical Engineering
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B Is length contraction (Lorentz transformation) an illusion or real?
My textbook (from first year university physics) says that length contraction is actually real. But how can it be real when two different observers can measure two different lengths? For example, if I am in a spaceship going close to the speed of light relative to people on Earth, they will...- student34
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- Contraction Length Length contraction Lorentz transformation Transformation
- Replies: 24
- Forum: Special and General Relativity
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Mechanical Waves Recorded after an Earthquake
.- Harli
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- Earthquake Length Longitudinal waves Mechanical Mechanical waves Speed Transverse wave Waves
- Replies: 4
- Forum: Introductory Physics Homework Help
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B Distance Length Contraction at Light Speed
I know it's not possible to travel at light speed so this is just theoretical. As I understand it at relativistic speeds the distance you need to cover to travel to a destination are length contracted. If you were traveling at light speed is the distance between you and any object ever zero?- MikeeMiracle
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- Contraction Length Length contraction Light Light speed Speed
- Replies: 1
- Forum: Special and General Relativity
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Arc length of vector function - the integral seems impossible
The vector equation is ## v(x)=(e^x cos(2x), e^x sin(2x), e^x) ## I know the arc-length formula is ## S=\int_a^b \|v(x)\| \,dx ## I found the derivative from a previous question dealing with this same function, but the when I plug it into the arc-length function I get an integral that I've...- overpen57mm
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- Arc Arc length Function Impossible Integals Integral Length Vector Vector function
- Replies: 2
- Forum: Calculus and Beyond Homework Help
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A Minimum sample length to estimate the frequency of a sinusoid
Given a discretely sampled horizontal sinusoid of length p, and unknown amplitude, what is the minimal number of consecutive points on a window that is required to correctly estimate its total length, starting at any random point on the wave? Initially I would think it would be either p (full...- MisterH
- Thread
- Estimate Frequency Length Minimum
- Replies: 17
- Forum: General Math
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Area of interior triangle of pyramid normal to a side length
This isn't homework, but I figured it's fine if I make it a HW problem and post here (if not, please let me know). Let ##z^*=0## be the vertex of the pyramid, and let ##z^*## run the altitude. It's easy to show the area of the base normal to the altitude is ##A = 4 \left.z^*\right.^2...- member 428835
- Thread
- Area Interior Length Normal Pyramid Triangle
- Replies: 3
- Forum: Precalculus Mathematics Homework Help
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MHB Find Vector of Given Length in Particular Direction
Question:- brinlin
- Thread
- Direction Length Vector
- Replies: 1
- Forum: General Math
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Understanding the Mass-Length Relation: Solving for V in Simple Equation
Hello, If i have this relation: ## M_p^2 = M^3_s V ## where ##M_p ## and ##M_s ## are masses in GeV and V is a length. Let ## M_p = 10^{18} ~ ## GeV and ##M_s = 10^3 ## GeV , what is V in meters ? My solution : The equation becomes ## V = 10^{30}## GeV , but ## 1 m \sim 10^{15} ~...- Safinaz
- Thread
- Length Mass Relation Unit conversion
- Replies: 6
- Forum: Introductory Physics Homework Help
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MHB :Calculating $k$ to Find Wire Length
$\tiny{2.5.1}$ Electrical Resistance of a Wire The electrical resistance of a wire varies directly with the length of the wire and inversely with the square of the diameter of the wire. If a wire 432 feet long and 4 mm in diameter has a resistance of 1.24 $\Omega$ find the length of a wire of...- karush
- Thread
- Length Wire
- Replies: 5
- Forum: General Math
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B Planck Length 1 Detector? Emitter?
Do we have the ability to detect the gamma ray of Planck Length 1? Is there any known phenomenon, natural or man-made, that could emit on Channel 1? How dangerous to man and machine would Channel 1 be / at what density (is that the right term?) would it become dangerous? Would there be any...- Silly Questions
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- Detector Length Planck Planck length
- Replies: 35
- Forum: Quantum Physics
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Measuring the length of a moving Beam in two different directions
v_g+v_e=15/t_1 v_g-v_e=10/t_2 v_g=s/(t_1-t_2) But there are too many unknowns. What am I missing?- kimiko333
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- Beam Length Measuring Mechanics Physics University
- Replies: 44
- Forum: Introductory Physics Homework Help
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I LIGO: Detecting Differences Less Than a Proton Length - How is It Possible?
I read that the LIGO detector in the US was able to detect a difference of less that the length of a proton, or maybe even less than this. How is this possible? The perpendicular arms won't be the same length down to the nearest proton length. Also, at such small lengths the microclimate on each...- thegroundhog
- Thread
- Gravitational waves Length Ligo Proton
- Replies: 5
- Forum: Classical Physics
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MHB Calculate the Length & Potential Energy of a Sliding Box on a Ramp
A ramp rises 10cm for every 80cm along the sloping surface. A box of mass 50 kg slides down the ramp starting from rest at the top of the ramp. The coefficient of friction between the ramp and the box is 0.03 and no other resistance acts. The box is traveling at 2 m/s when it reaches the bottom...- Shah 72
- Thread
- Box Energy Length Potential Potential energy Ramp Sliding
- Replies: 9
- Forum: General Math