Relationship Definition and 999 Threads

I'm wondering about the relationship between F=ma and E=mc2. Is it simply that, at relativistic speeds, E=mc2 replaces F=ma? (much like D = v x t is replaced by the Lorentz Contraction at relativistic speeds)

Recently I noticed something odd about the triangular numbers. The basic definition is \displaystyle\sum_{x=1}^{n}x=T_n A short time after playing around with T_n values I discovered something very odd-another formula for triangular numbers involving the root of the sum of cubes from 1 to n...

I was pondering Mars missions and wondered about what kind of vehicle an astronaut on Mars would need in order to get home. My first thought was that Mars gravity is .38 that of earth, so he would need a rocket about 38% as large to get off of Mars as he needed to get off of earth, This of...

Hi. I have no significant pure physics or math education or work experience (retired corporate analyst) but I was wondering what experts here might think about the relations between energy, dark energy and information. My understanding is that dark energy is the expansion of space, with space...

Fellow Nerds, I'm looking for a quantitative relationship between the gravitational strength of a point on a field and the speed of expansion of space at that point. Given a cosmological constant and a metric, is it possible to pinpoint a certain point of space and ask how quickly that space is...

Perhaps someone can clarify something for me that's been bugging me for a while. Assuming that singularities are not a singular event but occur naturally, we believe the objects for be of infinite density and infinite heat. On the other hand, in the case of black holes, it's logical to assume...

I would appreciate any clarification (or opinion) on the relationship between Quantum Numbers and Quantum Information. My question is related to the puzzle wether matter merely represents information or - at the basement level of reality - actually can be said to be information. Just to give...

Does anyone know the relationship between m, mass and c, the speed of light ? Can anyone draw the graph for me ? Thanks !

Hi, Am I right in saying that if the gradient of displacement is negative then stress is negative as in a simple elastic case, sigma = E*du/dx? thanks.

I've been teaching the Work, Energy and Power in UK A'Level Mechanics for some years without a problem. However, I got a question in class today which really made me think about my deeper understanding of the topic. I wonder if anyone can help with explanation of the problems below. The...

Is there any correlation between Mach number and Reynolds number? Both of these nondimensional numbers involve speed, but they don't seem all that related other than that. For high speed flow, we have high Mach number. Is it incorrect to say that "generally" high speed flow is turbulent?

I'm a games programmer working on a (simple, so far) physics engine for a driving game. Right now I'm interested in acceleration, and in particular trying to estimate the forces that go into it. I've got basic data for a bunch of cars (0-60 time, 0-100 time, top speed, mass) and a brute-force...

Homework Statement [/B] I have this system below. It is the schematic of a linear accelerometer moving horizontally, where m is the total mass of the slide, b denotes the viscous damping, and k represents the spring constant. The relative position between the moving mass and the case is...

Homework Statement A diffracting grating casts a pattern on a screen located a distance L from the grating. The central bright fringe falls directly in the center of the screen. For the highest-order bright fringe that hits the screen, m=x, and this fringe hits exactly on the screen edge. This...

I'm currently doing a report on Petrol Engines and I'm having a problem with my results not making sense. Am I correct in saying Break mean effective pressure (bmep) should increase as Engine Speed (rev/min) increases? My results do not reflect this and I don't understand why. I have attached...

Hey fellas! Nice to be here again [emoji5]️ Here is the thing, everybody at school keeps telling me that the more power consumed by an electrical component such as a resistor or even a coil the hotter it will get. However, even though I understand that power is energy per unit of time and heat...

I know,kinetic energy=##\frac{1}{2}####mv^2## But I saw one other equation it is kinetic energy=##\frac{1}{2}####|P.E|## Then I started looking for in which specific condition is it true?Because I know it is not always applicable .But I could not find that particular condition when it is true.So...

Hi there, I've recently been looking into applications of cross-correlation in the context of signal processing. I've noticed that the mathematical operations that yield the cross correlation between two signals is very similar to the operations in calculating the convolution of a signal and...

What is the relationship between the Fourier transform of a periodic function and the coefficients of its Fourier series? I was thinking Fourier series a special version of Fourier transform, as in it can only be used for periodic function and only produces discrete waves. By this logic, aren't...

A building has a water pipe inlet. I have found that at if I open the valve at this location fully, then I get 180 liters per minute at a residual pressure of 0,2 bars (static pressure is 5,4 bars). Is there a fixed relationship between the flow and pressure drop so that I can easily predict...

Hi, I am having trouble understanding the relationship between speed, distance and time. For example, if time was tripled, what would be the effect on distance? What about the effect on speed? Would they both increase 3 times as well? Thanks! All help is very much appreciated!

Homework Statement One object is dropped and falls for T seconds. Another object is dropped and falls for 3T seconds. Compare the distances fallen and their impact velocities, mathematically. Homework Equations v = d/t The Attempt at a Solution Just by reasoning it out, I know that the...

[FONT=Georgia]Hoping to clarify something about this... Is it fair to say that you should consider the relationship between pressure and area as a function of whether a fluid is moving or standing still? In other words, when a fluid is moving and you decrease the area, the pressure goes down...

Given the following: A directional radio wave transmitting antenna which creates a beam (diameter in mm), a current in volts, and a frequency (Hz), is it possible to calculate the em wave voltage (v/m or w/m2) immediately next to the antenna? and then at a distance of 10meters? What...

Hi all, I am trying to understand the meaning of "Direct Relationship" between two entities belonging to an ERD, i.e., an entity-relation diagram associated with a Relational database. A Google search did not return anything helpful. Say, A,B are the entities in question. I assume this...

What is the mathematical formula to calculate "a" for a given "b" in the picture below of a tetrahedron with sides "b" inside of a truncated tetrahedron with sides "a". I think that this is a more challenging problem that what it appears to be.

My daughter stump me on a question related to liters and grams in stoichiometry. Wondering if someone could help explain. First we know that 1 mole always eqauls 22.4 liters at STP. And 1 mole also always equals the selected element's atomic mass in grams on the periodic table. So... Let's...

Homework Statement Inq this question, I am given that the u dot ( rb x tb + re x w) =0. I knew that the rb x tb give a resultant moment pointed inside the book , which is parallel to AB... Then it cross with r AD, we will get the resultant moment. But when re x w , I will gt the moment...

I have just been studying Nullspaces... I want to make the following summary, will it be correct? C(A) is all possible linear combinations of the pivot columns of A. N(A) is all possible linear combinations of the free columns of A (if any exist). edit: I have a feeling these are...

Homework Statement The energy and pressure of black body radiation depend on T and V as Eq(1) & Eq(2). Suppose that the temperature and volume of a box of radiation change adiabatically. Find the relation between dE and dT in this process. Next, using Eq(1), show that T ∝V^-1/3 Homework...

1. Homework Statement 2. Homework Equations How to get ax=2ay? 3. The Attempt at a Solution a=10m/s2 And the solution I found was a=2m/s2 I found this at : http://www.physicstutorials.org/home/exams/dynamics-exams/142-dynamics-exam1

Homework Statement Let T be the tangent line at the point P(x,y) to the graph of the curve ##x^{\frac{2}{3}}+y^{\frac{2}{3}}=a^{\frac{2}{3}}, a>0##. Show that the radius of curvature at P is three times the distance from the origin to the tangent line T.Homework Equations R=1/K ##R=\frac{\left...

Homework Statement I am having trouble understanding what this picture is showing. [/B] I know that in the case of a sine wave, the voltage below zero will not conduct much if it does not drop past the breakdown region. On the other hand, it will start to conduct and grow exponentially at...

My group was the last one finishing the lab report for today's physics lab. The instructor asked why I didn't try more data point after I turned in the report. (The manual doesn't require a specific number of data point) I said I didn't really have enough time. He responded sarcastically, "Do...

Homework Statement There are 12 electrons spread on the circumference of a circle with radius R evenly. What's the electric potential at the centre? Then the electrons are concentrated on the upper half of the circle, spread evenly. What's the electric potential at the centre now? Homework...

A system at absolute zero (ground state) can't be be divided into observer and observed, can it? I'm struggling with the relationship between superposition, decoherence and temperature. Decoherence requires information. Information requires energy. Though multiple basis of "information" can...

Suppose that there's a wheel. A constant torque is applied to the wheel from the central axis. What is the relationship between the amount of force received by each particle on the wheel in relation to the distance each particle is away from the axis?

Homework Statement Write down the relationship between the linear frequency and the wavelength of a light wave when the wave is propagating in a medium of refractive index, n.[/B]Homework Equations wavelength x linear frequency = speed of light speed of light = refractive index x speed of...

I have Bathymetry data which gives the depth-area-volume relationship of a lake. I have determined the area-volume relationship using the function Area=A*Vol^B. Now I'm not sure how to determine the similar relationship between depth and volume. Can I use the same function i.e. Depth=A*Vol^B? I...

Hey,guys. I was confused by the building process of static electric field.There must exist some process building static electric field in the space. But what create it? How much time is needed? Is there any relationship with electromagnetic waves? Any one know this

The rate that a stationary clock slows down near a massive object, relative to one far away, can be read off from the Schwartzschild metric: $$c^2d\tau^2=\left(1-\frac{r_s}{r}\right)c^2dt^2-\left(1-\frac{r_s}{r}\right)^{-1}dr^2-r^2\left(d\theta^2+\sin^2\theta d\phi^2\right)$$ by setting...

I am a junior in high school and after I spent some time studying quarks and antiquarks, I continue to raise more questions about their relationship to other fundamental quantities. I tried searching the internet for answers but the posts I've been reading only raised more questions for me. Are...

[FONT=Times New Roman]E=keQ/r2 and V=keQ/r , I'm curious as to what what causes the relationship to r vs r2. I know the electric field is a measure of force per unit charge and the electric potential is a measure of energy per unit charge, just struggling to mentally connect where the inverse...

I should preface this question by saying that I am not familiar with Einstein's general relativity, so I am trying to understand the relationship between gravitational and inertial mass from a purely classical standpoint. Newton writes that the gravitational force exerted by an object is...

Homework Statement Suppose A^ and B^ are linear quantum operators representing two observables A and B of a physical system. What must be true of the commutator [A^,B^] so that the system can have definite values of A and B simultaneously? Homework Equations I will use the bra-ket notation for...

This is for work. I need to make a table for a client. What we did: had two different closed systems, only difference is material. We had frozen goods in both containers, the containers were both removed from the cooled surroundings they were in and placed outside. The temperatures were...

This is going to be a huge wall of text. I don't even know why I'm writing this. Probably just need to get this off my head. I don't see how any advice or comments can help me...I have lost count of how many times I have made this decision. I have been on the move from country to country ever...

Homework Statement Reginald is out for a morning jog, and during the course of his run on a straight track, he has a velocity that depends upon time as shown in the figure below. That is, he begins at rest, and ends at rest, peaking at a maximum velocity Vmax at an arbitrary time tmax. A second...

What is the relation between p max and mean effective pressure inside the cylinder

Hi, I have been tasked with finding a way to relate a bicycle tire's inflation pressure to its speed in traveling 160 meters. Data was given showing that as the pressure increased from 70 to 90 psi, the speed increased marginally. No equations were given. I think that it may have to do with...