String Definition and 1000 Threads

Homework Statement Ideal rubber stirng with length L=1km.Ant is takng a walk on the string with speed v=1cm/s After every minute(Δt=60s) ,string is getting longer by ΔL=1km. 1)Will ant get to the end of string? 2)If yes,then how long it will take ? Homework Equations 1) So i used...

When plucking a string once on a string instrument (a guitar for example), I can understand that this creates a disturbance in the form of a (actually two) pulses that travels along the string. It makes sense to visualize this. Let's for simplicitys sake say that the string is 1 meter long...

Homework Statement Hi, everyone. Me again. This time I'm here to ask about the tension in the string on a massive pulley. We have a wheel of radius R with a moment of inertia about its principal axis of 2/3 MR2 , suspended above the ground on frictionless bearings. A massless string of...

Homework Statement This is a prelab question which I hope for some confirmation I'm thinking right. A vibrating string is vibrating in the fundamental mode. The question is to plot a graph with a succession of applied tensions T on the x-axis and the resultant length L of the fundamental...

Homework Statement A fuzzy-dicer makes an angle of θ = 49.6° with respect to the vertical. The mass of the fuzzy dice is 1.0 kg. What is the tension? 2. The attempt at a solution (deleted answer)

Homework Statement An inextensible string of length ##\ell##, whose mass per unit length is ##\rho## is hung between two points at the same height a distance ##d## apart (##d < \ell)##. Using the Euler-Lagrange equations and the first integrals, find the shape of the string when it is in...

Which do you think are the most promising alternatives?

Homework Statement A mass m whirls around on a string which passes through a ring, as shown. Neglect gravity. Initially the mass is distance r0 from the center and is revolving at angular velocity ω0. The string is pulled with constant velocity V starting at t = 0 so that the radial distance...

I am doing a project on string theory and my first task is to work out fundamental string solution from the I(10) string action in NS sector.I am following A.Dahbolkar, G.Gibbons, J.A.Harvey & F.Ruiz Ruiz, Nuclear Physics B340 (1990) 33—55. Why is it called fundamental string? I have not taken...

1.This equation in the link below refers to the small angle approximation regarding deriving the wave equation from Newtons laws from small amplitude waves in a single string with fixed tension. 2.http://imgur.com/NGSwzcl 3. I'm a bit rusty on the maths and have no idea how these...

Collision -- a ball and string form a pendulum... 1. A 1.0-kg ball is attached to the end of a 2.5-m string to form a pendulum. This pendulum is released from rest with the string horizontal. At the lowest point in its swing when it is moving horizontally, the ball collides elastically with a...

Homework Statement Consider a string of length L held fixed at both ends. The string can be shaken up and down and, at certain frequencies, the result will be a standing wave pattern on the string. Find the five longest wavelengths (call them λ1, λ2, λ3, λ4, and λ5) of the standing wave...

Homework Statement Given that a string is constrained such that dy/dx = 0 at x = 0 and unconstrained otherwise, what is the reflected and transmitted power? y is the deflection of the string from the x-axis. y_1 is incident wave, y_r is reflected and y_t is transmitted. Homework Equations...

Homework Statement A ball of mass 125g is attached to a string .900 meters long. It is then set into vertical circular motion with 38 RPM. What is the tension of the string at the top of the circle and at the bottom of the circle? Homework Equations ∑Fy = may = marad arad = v2/R =...

So I made a banjo for my project and now I need to do the calculations. Well since its a string instrument I have to find the frequencies of the first four harmonics, I already have the fundamental frequency. Is it fine to use: fn = nf1 Not sure because I thought that was for open end air...

Hi all, The problem is shown below - but no answer was given to this, and the teacher did not plan on taking it up, since it was optional extra practice. My attempt at a solution: http://imgur.com/DmrgMMO, my final answer was 2.76 kg. I was wondering if this was right or wrong, and if...

Hi, I have a couple questions from chapter 2 of Zwiebach's A First Course In String Theory, second ed. 1) Zwiebach says [in the context of compact extra dimensions] "it seems very difficult, if not altogether impossible, to construct a consistent theory with more than one time dimension". Why...

Homework Statement Q .Find the tensions in the strings (1), (2) and (3) and the acceleration of the mass ‘m’ just after : (a) string (1) is cut (b) string (2) is cut (c) string (3) is cutHomework Equations The Attempt at a Solution I feel the answer should be (a) T1 = 0 ; T2...

Homework Statement In figure shown, pulleys are ideal m1 > 2 m2. Initially the system is in equilibrium and string connecting m2 to rigid support below is cut. Find the initial acceleration of m2? Homework Equations The Attempt at a Solution In equilibrium, 2T1 = T2 For...

Just started with physics, I am not very good. Homework Statement A weight with the mass m is hanging in one thread (C) that is connected to two other threads (A and B). Thread A is completely horizontal, while thread B is forming a angle of 45° with the horizontal plane. All threads are...

I am familiar with String theory and the Multiverse theory, but I didn't know that apparently String Theory points to a multiverse? Can anyone give insight to this? Also what do you guys think about the Multiverse theory? Personally it is far-fetched, but I am not dismissing it. I don't want to...

Homework Statement Hi! This is probably going to be a silly question, but I think I just need someone to point out my obvious mistake so I can go back and solve it properly. A semi-infinite string of density ρ and tension T has a mass affixed to the free end which is constrained to move...

Homework Statement An easily moveable, thermally insulated piston of negligible mass confines a sample of air of volume ##V_0=8\,\, \text{litre}##, at a temperature of ##T_0=300 K##, into a thermally insulated cylinder of cross section ##A=1\,\,dm^2##. The cylinder is fixed to a horizontal...

Homework Statement A solid uniform 50kg ball of diameter 30cm is supported against a vertical frictionless wall using a thin 35cm wire of negligible mass (the wire is attached to the wall, the ball is attached to the wire and rests against the wall). Make a free body diagram for the ball and...

Homework Statement Two masses M of the same amount are tied to two stings of length L and 2L. If both masses are swung in unison faster and faster, which string will break first? Homework Equations The formula I've been using is Tension = mv^2/r. The Attempt at a Solution My...

Homework Statement A string is wrapped several times around the rim of a small hoop with radius 8.00 cm and mass 0.180kg. The free end of the string is held in place and the hoop is released from rest. After the hoop has descended 60.0cm , calculate the angular speed of the rotating hoop and...

I am doing this problem: (a) Find the speed of waves on a violin string of mass 800 mg and length 22.0 cm if the fundamental frequency is 920 Hz. (b) What is the tension in the string? For the fundamental, what is the wavelength of (c) the waves on the string and (d) the sound waves emitted...

Homework Statement What is the tension of the string? Mass of piano string- 3.5g Lenght of piano string- 75cm Fundamental frecuency- 469Hz Homework Equations λ=2L/n ? Dont know where to start.

Homework Statement A string of mass M and length L is attached to walls at either end, and is under tension T. The string is held at rest in the following shape: y=B for L/2<x<3L/4 and y= 0 for the rest of the string. The string is released at t =0.(a) Find y(x, t). You may express your...

Hello, Homework Statement Two wires, each of length 1.8 m, are stretched between two fixed supports. On wire A there is a second-harmonic standing wave whose frequency is 645 Hz. However, the same frequency of 645 Hz is the third harmonic on wire B. Find the speed at which the individual...

Homework Statement Tension = 400 N Mass = 4g Length = .96m What is the speed of the wave on a string? What is the frequency of the 3rd harmonic? Homework Equations v=√T/(m/L) v=fλ The Attempt at a Solution v=√400N/(.004kg/.96m) = 310m/s...am I correct? f=v/λ...

1. Homework Statement Two particles of mass m are connected by a light inextensible string of length l. One of the particles moves on a smooth horizontal table in which there is a small hole. The string passes through the hole so that the second particle hangs vertically below the hole...

Homework Statement We have a stick which is vertical, its length is 2m and its weight 45.9kg. A string is pulling the top of the stick from the floor at a distance of 2m from the left of the bottom of the bar. A force of 100N is pulling from the right at the middle of the stick. Which has to...

Given a input string and 'n' random subsequences of that string , what is the probability of realizing original string using these subsequences correctly? Example : Given string = "MISSISSIPPI" Subsequences: 1) "MISS" 2) "III" 3) "MIP" 4) "SIS" 5) "IS" 6 ) "SP" 7) "MP"How many subsequences...

Not sure what section to put this in, so I'll put it here. Are there any good books on string theory that are good for someone who is a bit more than a layman (i.e. no extremely superficial, dumbed-down stuff), but still doesn't know more than single variable calculus and Newtonian mechanics?

Homework Statement I am posting three problems together as I believe they are quite short. 1.Show that the particle speed can never equal to the wave speed in a sine wave if the amplitude is less than wavelength divided by ##2\pi##. 2.Two wave pulses identical in shape but inverted with...

Hi there, I'm trying to understand the propagation of a pulse along a string that is fixed at both ends and am confusing myself. The demonstration I'm using is a long piece of string, tied at one end to the wall and with the other end held by my hand, putting the string under tension. Here's my...

I am reading in Halliday that the kinetic energy and potential energy carried by a wave in a string are both maximal at y = 0 (equlibrium position) and zero at y = A or r (maximal elongation). This sounds strange to me because usually KE decreases as PE increases and vice versa. Besides, if...

Dear all, In my textbook it is written that when a string clamped at both ends oscillates in it's fundamental mode then the frequency of the stationary wave set up in the string is given by f=v/2l .where 'f' means frequency,'v' means speed of wave and 'l' is the length of string.following are...

Homework Statement a light string is wrapped around a solid cylinder and a 300 g mass hangs from the free end of the string. When released, the max falls a distance 54 cm in 3.0s. b) calculate tension in string c) calculate mass of cylinder Homework Equations F=ma I=1/2(mr^2)...

Hello PF! Homework Statement A string is wrapped around the small cylinder as shown. You pull with a force F (and the cylinder does not slide). Calculate the acceleration of the cylinder CM (including direction). Here r = 3 cm, R = 5 cm, F = 0.1 N, and m = 1kg. [Make sure to define one...

How is the tension equal in both sides of the string, if the string is over a pulley with two different masses attached to its sides?

Hello, my name is Mike, and I have just enough electrical engineering knowledge to be dangerous. This season I have inherited a programmable LED Christmas light set up from my father-in-law who is no longer with us to help guide me with his EEngeneering knowledge. Here's the issue. I have...

A 2.0 kg block (m1) and a 6.0 kg block (m2) are connected by a massless string. Applied forces, F1 = 12.0 N and F2 = 5.0 N, act on the blocks, as shown in the figure below m1 is on the left side of the system, F1 is pulling on m1 to the left; m2 is to the right, F2 is is pulling m2 to the right...

Homework Statement Hello, I am a bit confused on when rotational kinetic energy exists and when linear kinetic energy exists. For example when we spin a string with a ball attached to the end it has kinetic energy of 0.5mv^2 of the ball when we were solving for velocity of the ball at certain...

Homework Statement The linear mass density of a non uniform wire under constant tension decreases gradually along the wire so that the incedent wave is transmitted without reflection. the wire is uniform for* -∞≤x≤0 In this region, a transverse wave has the form y(x,t) = 0.003cos(30x − 60t)...

I don't have any big programs. I just write programs to get me through my math classes. But I want to have the output look pretty. Like one program I have is for my finance class. prompt p if p = 1 then Prompt b,r,n,t r/100→x b/(1+x/n)^(n*t)→l disp l else Prompt b,r,n,t r/100 →...

Homework Statement A mass ##m## whirls around on a string which passes through a ring. Neglect gravity. Initially the mass is at distance ##r_0## from the center and is revolving at angular velocity ##\omega _0##. The string is pulled with constant velocity ##v## starting at ##t=0## so that...

Homework Statement Block's 1 (460g) & 2 (500g) are mounted on a horizontal axle of negligible friction (R = 5.00cm). When release from rest, block 2 falls 75.0 cm in 5.00s without the cord slipping on the pulley. a) What is magnitude of acceleration of blocks? b) Tension of T2 c) Tension...

Homework Statement I need to find a formula for the friction in the system. I had a disk and a pulley connected to a rotation sensor on each side. I wrapped a pulley with a string and there was a small mass attached to the bottom. As I let that mass fall, it would fall and spin a pulley...