Strings Definition and 523 Threads

This is not homework, I need someone to verify (9) and (10) below whether I am correct because I don't have the answer. I need to find the solution of the following: [SIZE="5"]Question Find the solution of the equation for damping vibration string stretched from x=0 to x=L where...

I am doing a question (its not home work just an exercise). The following is the question. Write code that allocates space for an 80-character string and then inputs a string from the keyboard and stores it in the allocated space. This is my code. #include <stdio.h> #include <stdlib.h>...

Homework Statement String 1 in the figure has linear density 2.4 g/m and string 2 has linear density 3.5 g/m. A student sends pulses in both directions by quickly pulling up on the knot, then releasing it. Consider the pulses are to reach the ends of the strings simultaneously. In the figure...

we sway into scifiction which i want to be realistic: How is it inside Subspace or Hyperspace or a cosmic string (from the perspective of different theories)? Can we even enter cosmic strings (if we say we had the technology)? Has the subspace (enbedded in our 4 dimensions) or the...

1. Homework Statement The problem concerns a block(mass M) hanging from a light string attached to a fixed support, that is pulled down with a force of the block's weight that produces an extension of 'l'. 2. Homework Equations The elastic P.E is half of (M*g*l).However the loss in...

Hello all. I am currently reading 'The Elegant Universe' and I'm puzzled by one key thing that is really starting to 'niggle' me! How can a one-dimensional string have multiple windings along a two-dimensional circular spatial dimension ("Garden Hose"). For this to be possible the string...

Beat frequencies/tension force of violin strings while tuning--please help Homework Statement To tune your violin, you first tune the A string to the correct pitch of 440 Hz, and then you bow both it and the adjoining string simultaneously, all the while listening for beats. While bowing the...

Hi there PF. For this problem I need to take the following code which apparently sorts an array with integers, and sort strings instead. However I DO NOT understand how this works for integers, much less how I could make it work for strings. Could someone please explain it to me? A few tips to...

So let's say you have like a pendulum but instead of the one string you have two strings attached to two fixed supports (I tried to include a picture). Let's say you pull it back and swing it so that it is swinging in and out of the screen. Would its period of oscillation be the same as if there...

What makes the strings in string theory "vibrate"? Does string theory include or say what is responsible for making strings vibrate? Also, why do the strings not all vibrate in the same pattern; what makes a string "choose" one pattern over another?

Could the higher dimensional spaces of string theory be used by point particles? Take the idea of extra dimensions of string theory and use point particles instead of strings. Point particles need some type of internal degrees of freedom? Thank you for any help.

1.AB is a uniform bar of length 5m and weight 60N. It is supprted in a horizontal position by 2 vertical strings P and Q. P is 0.5m from A and Q 1.5m from B. a) What are the tensions in the strings? b) What weight must be applied at A if the tensions in the strings are to be equal? c) What is...

Homework Statement Two wires are tied to the 300 g sphere shown in figure. The sphere revolves in a horizontal circle at a constant speed of 6.50 m/s. What is the tension in the upper wire?What is the tension in the lower wire? Write an equation for the sum of the forces along y. Use it to...

Motion of strings may give rise to particles? Size difference about, E-35m/E-15m = E-20 Motion of particles gives rise to Universe (or Universes?)? Size difference about, E-15m/E26m = E-41 Thanks for any help.

Homework Statement You have three strings holding a 20kg weight, all tied to a ceiling above the weight, one centered right above the weight, the other two tied to the string at equal angles. What is the tension in each of the cables Homework Equations Fnet=0 The Attempt at a Solution...

1. Homework Statement : A 4.00 kg object is attached to a vertical rod by two strings (as below). The object rotates in a horizontal circle at constant speed 6.00 m/s. mass = 4.00 kg V = 6.00 m/s Homework Equations centripetal acceleration = Ac Ac = V^2/r...

so i came across string theory and i don't understand (if your going to go along with it) why it is tiny strings that make up the universe and why exactly do they have to exist in more then 4 dimensions?

This is a old one, but it is rare to find the general solution: Consider a string (a fuse) that, when burned from one extreme, takes one hour to burn, but irregularly (some pieces burn faster than another). Get two strings of this kind. The irregularities are different, you are only granted the...

Homework Statement The string connecting the m1 and the m2 passes over a light frictionless pulley. Given m1 = 6.51kg, m2 = 7.48kg, m3 = 9.75kg. The acceleration of gravity is 9.8 m/s2. 1) Find the downward acceleration of m2 mass. Answer in units of m/s2 2) Find the tension in the string...

Homework Statement A 100-N body is shown suspended from a system of cords. http://bcs.whfreeman.com/WebPub/Physics/tiplerphysics6e_bridge/question_bank_images/4-50A.png?2417 1. What is the tension (T2) in the tilted cord? Round your answer to three significant figures. 2. What is...

If a string has a Planck length then why doesn't it have a huge Planck mass? Perhaps it does but its negative gravitational self-energy counteracts this huge positive mass/energy. Maybe a closed string can be thought of as a Planck energy electromagnetic wave trapped by its own...

If you have a guitar string and you pluck it nothing happens. Not unless it is tensioned by pulling both ends tightly. In string and brane theory do the strings have something that keeps them tensioned? Or don't they need tension to maintain vibrating; unlike normal strings? Are they free...

After compiling the code below, GCC says that you can't compare a pointer to string by iso C++ standards. But I don't see a pointer anywhere (I don't know pointers for now...did it long ago, now forgot)...may be it has to do with the fact that arrays are called by reference. char...

In string theory are the strings themselves the manifolds? or are the strings vibrating in a 10 or 11-d manifold?.

This is what a book says. Is this string different from a text stream which consists of many lines?...or can a string contain many lines separated by \n?

For 30 years string theorists have said string theory is the only game in town. It is the only known consistent theory of quantum gravity. LQG has not been shown to have GR in the low energy regime so it is not been shown to be even related to gravity. The only reply I've seen is that string...

I've recently had this thought experiment, and wanted to share it. My HS physics teacher had talked about "perfect" strings that had no mass, does not stretch, and is completely flexible when describing physics experiments. Using such a hypothetical string means it does not interfere with the...

I know that answers to the following can sometimes be subjective and biased... but still... What are the most 'promising' models in string theory, judged by the potential realization of a realistic SS standard model? Also, in particular, how do Intersecting Brane Models (since their...

Consider a character string randomly generated from an alphabet {T,H} of length L, where T and H each have a probability of 0.5. For an arbitrary finite L the probability of a given string is p=(0.5)^L. A probability is the sole determinant of Shannon entropy (S). Therefore I'm claiming that...

Is there something in string theory that requires strings to be the most fundamental structure?

Homework Statement Four blocks are on a horizontal surface. <---F2---B---Tx---A---Tz---D----Ty--C---F1--> The blocks are connected by thin strings with tensions Tx, Ty, Tz. The masses of the blocks are A=41.0 kg, B=21.0 kg, C=29.0 kg, D=39.0 kg. Two forces, F1=47.0N and F2=71.0N act on...

Homework Statement Two objects of equal mass m are whirling around a shaft with a constant angular velocity ω. The first object is a distance d from the central axis, and the second object is a distance 2d from the axis. You may assume the strings are massless and inextensible. You may ignore...

Mi imaginery of a oriented string is a line with two different (oposite) ChenPaton labels pasted in the extremes, say +...- while an unoriented one has the same label pasted in both extremes, say +...+ or -...- In this imaginery a vacuum loop for oriented strings would create two strings...

Homework Statement One string of a certain musical instrument is 79.0cm long and has a mass of 8.79g . It is being played in a room where the speed of sound is 344m/s . A)To what tension must you adjust the string so that, when vibrating in its second overtone, it produces sound of...

I've watched a few documentaries about string theory, read about it, heard people talk about it. But I cannot visually grasp what the heck strings look like. Physicists (maybe not all of them but the ones I only hear) like to say stuff like that if you pluck a guitar string you get a certain...

I have an assignment for my CS class. It is the following: * * complete the function: * * timesFound(string searchIn, char searchFor); * * The function should return the number of times the * character searchFor appears in the string searchIn. * */ int timesFound(string...

Homework Statement In a rescue, the 72.0 police officer is suspended by two cables, as shown in the figure below. Homework Equations T = mgsin(48)? T2 = mgsin(35)? The Attempt at a Solution I used the above equations and it is not right. Me and my friend have been working on...

By definition, D(irichle)-branes are branes on which open strings end. Then how closed string theories IIA and IIB may contain D-branes? Or more precisely, why the branes appearing in closed string theories are still called D-branes?

Just like you can create the ilusion of superluminal motion by projecting a flashlight into a wall, some strings would be projected into tachyons. Has anyone heard or thought about that?

Homework Statement A string 44 cm long will break under a tension of 24 N. Two such strings are tied to a 670 gm rock, their ends 60 cm apart. The rock is spun between them. What is the maximum speed it can spin before the string breaks? (Using pythagorean theorem, you can determine the radius...

Hi all ! I am curious about the possibility of knotted strings. If we can accept the propagation of closed loop strings, then shouldn't we consider the possibility of knotted, closed loop strings ? I do not see - offhand - any reason why a closed string cannot be knotted. Think of a...

Anyon are particular 2 dimensionsional objects and so is the worldsheet critical superstrings. But given that those 2 are extemely fashionable nowadays, and they happen in this dimension, I am extremely surprised to find that anyone didn't try anyonic strings. That is, instead of supersymmetric...

Petr Horava attempts to start at this paper a small quantum gravity theory, like Loop Quantum Gravity, except that he, according to his words: http://arxiv.org/abs/0901.3775v1 "In analogy with Yang-Mills, we are motivated to look for a “small” theory of quantum gravity in 3+1 dimensions...

Why do strings only have one dimension (or maybe branes have 2 dimensions)? Why aren't oscillating volumes (like a cube) used?

Homework Statement Ok, i need to make a program that will search for a substring in a given string, and replace it with another one.The Attempt at a Solution #include<stdio.h> #include<iostream> #include<string.h> using namespace std;int fsubstitute(char *ulazni, char *prvi, char *drugi)...

Hi I know I have been asking many questions. It seems this stuff is a lot more difficult than I thought so: 1.) Is the Quantum Field the field responsible for the creation of forces and particles, if not what does it say in a nutshell. 2.) If there are parallel universes do they affect...

My question is simple and straight forward - how does a 1-dimensional string "convert" to a zero-dimensional point particle? And another one - for the purposes of physics, energy is not a physical object but an abstract mathematical construct. So how can a string of energy have a definite...

Homework Statement A 30-cm long string, with one end clamped and the other free to move transversely, is vibrating in its second harmonic. The wavelength of the constituent traveling waves is: A) 10 cm B) 30 cm C) 40 cm D) 60 cm E) 120 cm Homework Equations L =...

Homework Statement Given that the ASCII character system has 128 possible characters how many 5 character strings are there with at least one occurence of the '@' symbol. Homework Equations The Attempt at a Solution So clearly which symbol we're using doesn't matter, and I see...

Homework Statement A 119 mass hangs from two string Calculate the tension in both strings. Let θ1 = 77.0° and θ2 = 26.0 degrees Homework Equations Fnet=ma The Attempt at a Solution This is the last question of my homework packet (so its the most challenging) and I have no clue how...