String Definition and 1000 Threads

Homework Statement a ball was hanging by an inextensible string to a small airplane. firstly, it was hanging straight down but when the pilot started the motor the string made an angle of 30 degrees wrt the vertical. Assuming that the ball is a point mass, find the acceleration (m/s²) of...

hello I'm a beginner in c programming. I wrote a code that converts the lower case that the user entered to upper case characters. I want to improve my program , but since I'm a beginner i might not be aware of some technics . my program can only allow you to enter as many characters as...

Homework Statement A musician frets a guitar string of length 1.5 m at x = 0.34 m with one finger, and simultaneously plucks the string at x = 0.17 m with another finger (raising it to a height h = 2.1 mm. Both fingers are simultaneously removed from the string, and it is allowed to vibrate...

If a car with no acceleration, only velocity, hits my spring with a spring constant K What will be the deformation in string? How do I calculate the force from impact while acceleration is equal to 0?

1. Two blocks made of different materials connected together by a thin cord, slide down a plane ramp inclined at an angle θ to the horizontal. The masses of the blocks are mA and mB and the coefficients of friction are μA and μB. PART A If μA < μB, determine a formula for the acceleration of...

Is the relationship between the length of a guitar string and the frequency of the pitch it produces a linear relationship? e.g. If the frequency of the pitch of a string is 60 Hz and I halve the length, should it produce a pitch with a frequency of 120 Hz? This is assuming all other...

Homework Statement A 200 gram body pierced string can slide through a 1.8 m string, tied at points A and B to a vertical rod around which rotates so that the segment BC is flat. Calculate the speed of the body. I don't know where I have to put the body to solve the problem. Here is the...

If I pluck a string, a wave begins to propagate throughout the string. From experience we know that this produces a sound and this is due to the fact that the oscillation of the wave in the string causes air molecules in its vicinity to oscillate similarly. The speed of the wave in the string...

Homework Statement Homework Equations The Attempt at a Solution The 4 main equations are equations (1), (2), (7) and (8). But I can't seem to isolate A5 alone as solving equations (7) and (8) will make A5 disappear.. I got the relation between A1, A2, A3 and A4 but still no A5..

Hi everyone. I'm interested in computational science but have an interest in string theory as well as I'm sure a few people here do. My question is does computational science have a place in the research for string theory? Would a physicist simply give some numbers for a computational...

Homework Statement Homework Equations The Attempt at a Solution

Hello, I don't understand the second question, i don't know what I have to do: Homework Statement A string of length L, which is clamped at both ends and has a tension T, is pulled aside a distance h at its center and released. (a) What is the energy of the subsequent oscillations? (b)...

Homework Statement Two waves are propagating in a long uniform string of linear mass density μ and tension Fτ. Their equations are: y1=A1cos(k1x-w1t) y2=A2cos(k2x-w2t) Known: λ1 (wavelength of y1), λ2, A1, A2 what is the vertical velocity of the string at x=2m and t=5s...

Homework Statement A bar with mass m and length l is attached at one end to a string (also length l) and is swinging back and forth. Find the normal modes of oscillation. Homework Equations L=T-U, and the Lagrange-euler equation, I=(1/12)ml^2The Attempt at a Solution So my idea is this. Use...

Homework Statement A guitarist has a problem that the E-string (330Hz) often breaks when tuning it. The string is made of Copper and it has a diameter of 0.3mm. After some quick calculations based on the length of the guitar neck we can determine that the wave velocity is 530m/s It is known...

Probably a bit abstract,but I was thinking if 4D closed strings could form knots? I mean if a closed string in 4-dimensional spacetime can be considered an unknot and a knot polynomial be associated with every closed string. I also wondered that if the fundamental strings vibrate in the knotted...

Homework Statement Two particles of masses 8 kg and 5 kg are connected to the two ends of a light inextensible string which passes over a fixed smooth pulley. Initially each of the two particles are held at a position which is 5 m above a horizontal ground. The objects are then released from...

Homework Statement A light elastic string has a natural length 1 m. One end of the string is attached to the fixed point O and a particle P of mass 4 kg is suspended from the other end of the string. When hanging in equilibrium, P is 1.2 m below O. #1 Find the modulus of elasticity of the...

Homework Statement Two particles A and B, of masses 2m kg and m kg respectively, are connected by a light inextensible string which passes over a fixed smooth pulley. The system is RELEASED from REST, with both portions of the string vertical and taut, while A and B are at the SAME HEIGHT. 1...

Image included to show I've made an attempt, but my attempt left me realising I just don't know where to go. If someone could point me in the right direction, it'd help a lot.

I have a question about the paper: C. G. . Callan, R. C. Myers and M. J. Perry, “Black Holes In String Theory,” Nucl. Phys. B 311, 673 (1989). I have attached the relevant section. I am having trouble using equations (2.1) and (2.4) to derive (2.5) and (2.6). When I do the calculation...

Does string theory, in principle, answer why matter comes in "chunks"? Does string theory, in principle, answer why matter comes in "chunks" of the same amount (say the mass of an electron or muon), and why the energy in the electromagnetic field of a given frequency also comes in a "chunks"...

In covariant quantization of the string, say as in David Tong's http://arxiv.org/abs/0908.0333 (p28), time is an operator. Is the time operator Hermitian, and does it correspond to an observable?

When making the transition from the dispersion relation for a beaded string to the relation for a continuous string, I'm confused about the following issue. Take a to be the spacing between beads, m the mass of each bead, and T the tension in the string. We assume these to be constant. For the...

Right, Hello, I am new to this, and do not have much understanding, but can someone here help explain the Dimension Models and String theory to me?

For quark anti-quark binding the potential takes the form: V(r) = -k/r + σr Where the first term comes from the Coulomb force and the second term comes from the strong nuclear force. My question is whether σ is the same for all quark anti-quark pairs or if it's different depending on...

1. Homework Statement : A rock of mass m is attached to a string of negligible mass and length L. The rock is released from rest from a horizontal position. When the rock is at point P, the string attached to the rock makes an angle θ with the horizontal. In terms of the quantities, m, L, θ and...

Hi, Can anybody explain how by giving an vertical impulse to a string you can cause a transverse wave. What is confusing me is that you just give the string an impulse upwards, where does the energy transferr horizontally come from? By picturing that all the Points of the strings are connected...

Homework Statement A 210 g bucket containing 12.5 kg of water is hanging from a steel guitar string with mass m = 8.58 g, density p = 7750 kg/m3, and diameter d = 1.00 mm. A) When the wind blows, it causes the cord to vibrate at what resonant frequency? B) Suddenly the bucket springs a leak...

LQG, strink theory and Penrose's spinor theory, or maybe it's twistor theory, I don't know, all I know is that all three theories achieve mathematical miracles in their attempts to go beyond the Standard Model - how can all three theories do this but be mutually exclusive at the same time. Or...

Hi everyone, I've always wondered what's that fuss for unifying general relativity and quantum mechanics all about. I stumbled upon things like string theory(or M theory) and even loop quantum gravity( which I think is as good as string theory despite rumors). My...

Homework Statement Find the tension in string 1 I don't get the same answer as the solution manual. My attempt: The y-component of string 2’s tension must equal the weight of the block. The x-component of string 2’s tension must equal the tension of string 1. T1=T2x=T2y/tanθ =23°...

Homework Statement I keep getting the wrong answer for this question: A taut spring for which μ = 0.05 kg/m is under tension of 80.0N. How much power must be supplied to the string to generate sinusoidal waves at a frequency of 60Hz and an amplitude of 6cm? Homework Equations ω = 2∏f...

"Foundations of physics" Special Issue: Forty Years of String Theory http://www.springer.com/physics/history+&+philosophical+foundations+of+physics/journal/10701 If this has already been mentioned feel free to delete this post. Articles free through march, A Critical Look at Strings (Carlo...

Given an action for a 5-brance ##S=\int d^6x\left[\sqrt{-g}{1\over {4\partial_r a\partial^r a}}\partial_ma(x)F^{*mnl}F_{nlp}\partial^pa(x)+ \sqrt{-\det(g_{mn}+i\tilde F_{mn})}\right],## where ##x^m## ##(m=0,1...,5)## are local coordinates of the worldvolume...

Homework Statement problem 4.4 The question: http://ocw.mit.edu/courses/physics/8-03-physics-iii-vibrations-and-waves-fall-2004/assignments/ps4a.pdf The solution: http://ocw.mit.edu/courses/physics/8-03-physics-iii-vibrations-and-waves-fall-2004/assignments/sol4a.pdf...

Homework Statement A 4-kg rock is tied to the end of a string and twirled overhead, 1.6 m above the ground, in a 1.1-m radius, horizontal circle. The string is known to break if its tension reaches a value of 514 N. The rock it rotated faster and faster until the string breaks. How far...

Homework Statement Given the tension T and unit mass per length U of a string what is the speed of sound along the string Homework Equations The Attempt at a Solution I know how to find the propagation speed of a transverse wave on a string, is that the same as the speed of...

This question is literally driving me crazy. How does the String or rope or whatever is used in a Foucault pendulum not twist with the rotation of the Earth (because the rope is attached to bases that are attached to the ground). Actually if the bases are attached to the ground, that should...

I'm trying to learn more about the physics of guitars. I followed through the derivation of the transverse wave equation and that makes sense, but it seems like several of the simplifying assumptions might not apply. There are a lot of approximations with small angles and small slopes. I...

I'm working on my physics lab and I'm confused by the equation that they provide. μ=\frac { 1 }{ { (2Lslope) }^{ 2 } } What exactly does slope represent here? Also, what is the typical linear mass density of a string? I'm getting 0.673 grams per meter. Is this right? Edit: Never mind about...

Homework Statement A gymnast of mass 59.0kg hangs from a vertical rope attached to the ceiling. You can ignore the weight of the rope and assume that the rope does not stretch. Use 9.81 m/s^2 for the value for the acceleration of gravity. Calculate the Tension, T, in the rope if the gymnast...

Problem Two small identical small spheres with mass m are hung from insulating threads of length L, as shown in the figure. Each sphere has the same charge q1 = q2 = q. The radius of each sphere is very small compared to the distance between them, so that they may be considered as point...

Calculate the tension in the cable connecting the two masses. Assume all surfaces are frictionless. FBD m1 = 5 kg θ1 = 60° m2 = 6 kg θ2 = 70° Equation 1 ~ FT - Fg = ma FT - mgSinθ = ma FT = 5a + 5(9.8)Sin60 FT = 5a + 42.44 Equation 2 ~ Fg - FT = ma...

I have been following Dr. Michio Kaku and his ideas on string theory. My question is, with the addition of other dimensions, what types of experiments and/or results could possibly provide evidence that this theory is correct. If we currently can't perceive these "discrete" dimensions, what...

A string with a density/length of rho and tension T has an elastic spring with stiffness k at x=0. There is a step pulse (fi = H(t)) incident on this discontinuity. Determine the reflected and transmitted waves. Im not sure what boundary condition to use at the location of the spring. All...

Homework Statement Homework Equations Energy The Attempt at a Solution So I'm not exactly sure what this question even wants considering the statement is true by the work - energy theorem. Does it want me to show it explicitly for this case? If so, then, since there are no forces...

Homework Statement See: http://www.aapt.org/physicsteam/2010/upload/2010_FmaSolutions.pdf Question 11Homework Equations T_net = 0 F_net = 0 The Attempt at a Solution Start with F_net = 0: Let T1 be the force of tension on the left, T2 on the right T1cosθ=T2cosθ Y components: T1sinθ+T2sinθ = mg...

Don't know if it is a homework question or not but it was a friend asking me and I feel ashamed because I am engineer but I don't know. When whirling a supplied mass on a string in a horizontal circle with constant speed. Assume that the mass of the string is negligible compared to the mass...

Hello! I couldn't find any answer to a wondering I have: On one end of a light string, attach a heavy ball, and on the other end of the string hold it with your hand and whirl around the ball-on-string. You reach a high rotational speed and finally the string breaks at the string-ball...