# Questions tagged [string]

This tag is for non-relativistic material strings, such as, e.g., a guitar string. PLEASE DO NOT USE THIS TAG for relativistic strings and string theory.

1,143 questions
Filter by
Sorted by
Tagged with
17 views

### Particle dynamics (mechanics), inclined plane, pulley, two blocks [closed]

The angle between the inclined plane and the surface is α. The coefficient of friction between block 2 and the inclined plane is k. Find the ratio inequality of m1 over m2 that the system remains ...
159 views

90 views

### Effective mass of pulley system [closed]

Below is the original problem: A particle of mass $3m$ is connected by a light inextensible string passing over a smooth, fixed, pulley to a smooth pulley $P$ of mass $M$. Over this pulley passes a ...
3k views

### Magnetic field changes induced by vibrating electric guitar string

Here is a picture (from a paper by Feinberg and Yang in the Journal of the Acoustical Society of America) of an electric guitar string vibrating (mostly in the $y$ dimension) near a permanent magnet. ...
82 views

1 vote
50 views

### Potential energy term in lagrangian of waves on a string

I'm going through Quantum Field for the Gifted Amateur, in example 1.4, the wave equation is derived through the Lagrangian. A key fact used is that, the potential energy equation is given as:  V = ...
564 views

### Why does a rope attached to a block move when pulled?

In the diagram above, person $P$ is pulling block $B$ by a massless rope $R$, and they are all accelerating in the indicated direction. If the force that $P$ applies to $R$ is $F_{P,R}$, then to my ...
54 views

### Why should the tension be constant throughout if there is external force? [closed]

I came across a question from Pathfinder for Olympiad. The question was: A frictionless non-conducting inextensible thread of length l wears three beads of positive charges q1 , q2 and q3. The ends of ...
43 views

### Forces of an elastic closed string

I want to calculate the forces acting on an element of a closed elastic string and derive a wave equation on a closed string. For this I have already figured out that if the closed shape of the string ...
452 views

### How to create a standing wave that doesn't oscillate with the fundamental frequency?

Is there a way to make the string on my violin vibrate in an overtone frequency instead of the fundamental frequency?
1 vote
72 views

### How tensions of $y$ axis are different, but overall tension still the same?

Let's say rope is at equilibrium and both ends are attached to something(boxes). We put a finger on it and let go. So it starts accelerating upwards. Let's consider just a tiny, tiny piece of the ...
94 views

### How to understand the larger than $g$ acceleration of the free end of a falling chain?

In this article I read that the acceleration of the free end of a falling folded chain is greater than $g$, but I cannot really understand why. Why isn´t the acceleration just $g$ since it is a free ...
35 views

### Analysis of simple pulley system

I have some questions about the motion of the simple pulley system illustrated in the book Machinae novae. Are the following conclusion about the system correct? Since the length of the rope is ...
1 vote
90 views

### What does disc sliding over a string means in this system? [closed]

I was studying Newton's Laws of Motion and my book gives a diagram in order to explain what components together can or cannot be considered a system in the figure given below. Now it says we cannot ...
49 views

### An elementary question on blocks and string [closed]

I have a doubt in one of the problems, I came across in a book. Though I searched answers for it, I was not able to develop a satisfactory understanding. The question asks us to draw a free body ...
1 vote
532 views

### What is actually the clear, precise and world-wide accepted definition of TENSION FORCE?

This is a long post, but only because I have explained the scenario very very clearly,90 percent of this post is explaining you a simple situation,my doubt is only 5-6 lines at the very end of this ...
92 views

### What is the reaction force when I "push" a string/rope/wire of some mass $M$?

Consider a situation like this There is a rope of uniform mass $M$ whose one end is attached to a wall. Obviously, the gravitational force $mg$ and normal force are acting on it in vertical direction ...
84 views

### Tension in a violin string

Say we have a string of fixed size on a violin. If I were to play it open (without pressing down on it) it would vibrate at a certain frequency. If I were to play it whilst pressing down on the middle,...
93 views

### (Physics 2, Waves) Why does $\tan(\theta) = dy/dx$? [closed]

In the following example: At the very last step, how does the author get that $\tan(\theta) = dy/dx$? To which $dy$ and $dx$ is this referring to? It can't be the same $dx$ that is labelled in the ...
91 views

### Why In the below diagram, the force causing torque on disc is $T$ not $T+mg$?

please see the image attached, I have to calculate torque acting on the disc, and my teacher took the force causing torque T not T +mg, I think it should be T +mg because that block is also exerting ...
81 views

### Normal contact force, friction

If two blocks are resting on top of each other and are on the ground, the weight of the upper block causes an equal and opposite reaction force on the lower one (Newt 3rd) and the same happens for the ...
1 vote
73 views

### Relation between frequency of vibrator generator and frequency of waves in a stretched string

Imagine a vibration generator is attached to a stretched string. Will the frequency of the vibration generator be equal to the frequency of the waves produced in the stretched string? Also, a similar ...
1 vote
30 views

### Change in kinetic energy of mass pulley system [closed]

Imagine a pulley (with non-negligible mass) with two masses hanging from the pulley on a rope on opposite sides. One mass is accelerating downward and the other mass is accelerating upward. We assume ...
1 vote
94 views

### $F=\frac{dp}{dt}$ for falling chain [closed]

There are several questions on Physics SE regarding the problem of a falling chain. However, to the best of my knowledge, no one has yet asked the following one. Consider the scenario presented in ...
180 views

### Why does a Foucault pendulum need to swing?

Let's imagine a Foucault pendulum placed at the North pole of the Earth. If it is oscillating, we know that the plane of the oscillation will stay fixed with respect to distant stars while it would ...
4k views

### Why is the work done by the tension in a pendulum string zero?

Isn't the string pulling the ball upwards, and, therefore, doing work on the ball, like when someone lifts weights. I understand that the force is perpendicular but can I get an intuitive answer as to ...
I understand that Hooke's Law is $F=-kx$, and that this law only applies when a spring is not "overstreched." However, does Hooke's Law apply to all springs, or only simple harmonic ...