An object such as a metal coil or air-filled tube which provides a force opposing the direction of deformation.

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5answers
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Is the spring constant k changed when you divide a spring into parts?

I've always been taught that the spring constant $k$ is a constant — that is, for a given spring, $k$ will always be the same, regardless of what you do to the spring. My friend's physics ...
12
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4answers
1k views

Is there a deep reason why springs combine like capacitors?

I was solving a practice Physics GRE and there was a question about springs connected in series and parallel. I was too lazy to derive the way the spring constants add in each case. But I knew how ...
8
votes
2answers
448 views

What will be different if the spring is not massless?

In almost all text, it uses the massless spring as example to illustrate the idea of elastic potential energy. I wonder what's really being changed if we consider the mass of the spring? I saw a ...
7
votes
2answers
13k views

How much force is in a keystroke? (estimated, of course)?

I'm a software developer, and I need to calculate the estimated amount of force expended typing stored text. Preferrably in some interesting way. (i.e. the force exerted on keys thus far is enough to ...
7
votes
2answers
771 views

Forget Hooke's law. Why does a spring exert a force?

Forgetting Hooke's law for a minute why, from a microscopic perspective (preferably quantum) on up to a macroscopic one, does a spring under tension exert a force? I was thinking that there might be ...
7
votes
4answers
1k views

How far does a trampoline vertically deform based on the mass of the object?

If a baseball is dropped on a trampoline, the point under the object will move a certain distance downward before starting to travel upward again. If a bowling ball is dropped, it will deform further ...
6
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4answers
1k views

Why does a ball bounce lower?

If a ball hits the floor after an acceleration then why does it bounces lower? I mean the Energy is passed to the floor then why does the floor give back less Energy?
6
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2answers
166 views

What can be known about the formulas for energy only from the fact that it is conserved?

The question is to figure out how the energy can be derived knowing just one thing: There is a quantity called Energy that is conserved over time. The goal is to get an equation that somehow ...
6
votes
1answer
725 views

Slinky base does not immediately fall due to gravity

Why does the base of this slinky not fall immediately to gravity. My guess is tension in the springs is a force > mass*gravity but even then it is dumbfounding.
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2answers
284 views

Nonuniform acceleration due to rubber rope

What I want: I have a rubber rope which is $5m$ in length when not stressed and is able to stretch about $100\%$ (to $10m$ long). I want to accelerate a constant mass horizontally, which has ...
5
votes
2answers
185 views

Forced harmonic oscillator with two springs

Consider a vertical system of two springs in series, with a mass(50 g) between them. From below the system is driven by a vibration generator. The setup is shown here, but the picture is taken while ...
5
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1answer
292 views

Finding coefficient of proportionality

Recently in my AP Physics class I did a lab in which I measured k for a spring by setting up an oscillating system with it, and timing the period, repeating for different masses. Since ...
5
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3answers
365 views

How does the shape (form; not cross-section) of a spring impact performance?

Cylindrical compression springs are everywhere and then some applications choose other forms like rectangular or unique polygonal form. What impact does the form of a compression spring have and how ...
5
votes
1answer
642 views

How does spring constant change with resistivity changes

I want to create a set of silicon based materials that have been doped with different materials and/or different amounts of dopants. The purpose of this is to see how the spring constant of silicon ...
5
votes
2answers
589 views

Tricky spring on a surface question

I have this relative simple-looking question that I haven't been able to solve for hours now, it's one of those questions that just drive you nuts if you don't know how to do it. This is the scenario: ...
4
votes
2answers
412 views

Potential energy of a spring

I'm puzzled about the potential energy of a spring. A spring is a conservative system. So the potential energy should be defined only up to a constant -- can be defined to be 0 anywhere. However, ...
4
votes
1answer
1k views

Hooke's Law question

I have the following question to answer: a force of160 N stretches a spring 0.050m from its equilibrium position. A. what is the spring constant of the spring? The equation for Hooke's Law in my ...
4
votes
2answers
956 views

Why is the damping force on a spring oscillator linearly dependent on velocity?

If you consider the damping force is friction like in: then the force should be $$F=\mu N$$ where $\mu$ is the coefficient of kinetic friction. Why then is the damping force assumed to be linearly ...
4
votes
1answer
88 views

Faster than critical damping for harmonic oscillator?

The image below shows damping for spring oscillator with Hooke law F=-kx and damped with F=-cv where: k is spring constant x is oscillator position c is damping coefficient v is velocity of oscillator ...
4
votes
1answer
650 views

What is the effective spring rate of a magnetic spring

Consider a magnetic spring as seen on this YouTube video, but ignore gravity. If I wanted to calculate the effective spring rate (Force vs. Deflection) curve for the top magnet, how would I go by ...
4
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3answers
4k views

If you place a spring on a neodymium hard-drive magnet, it appears to vibrate in slow-motion. Why is that so?

By chance(playing around really) I saw that a spring(mainly from a pen) placed on a neodymium hard-disk magnet(and then flicked by your finger at the top) makes a nice-effect (see youtube video ). It ...
4
votes
1answer
175 views

How to calculate the new positions of other vertices in spring-mass system graph, when one vertex is actively moved by the user?

I am developing an android based game. I have 10 soldiers uniformly spaced in the scene using some kind of formation. Example - banks of 3 3 and 4 or banks of 4 4 2 or banks of 4 2 and 4 etc... Now ...
3
votes
3answers
203 views

Wrong calculation of work done on a spring, how is it wrong?

So I would have thought that this would be how you derive the work on a spring: basically the same way you do with gravity and other contexts, use $$W=\vec{F}\cdot \vec{x}.$$ If you displace a spring ...
3
votes
2answers
3k views

oscillations of blocks connected by a spring

Imagine two blocks of masses $m_1$ and $m_2$ joined together by a spring of spring constant $K$. Now let the spring be stretched by a distance $X$ and then the system is released. suppose during the ...
3
votes
2answers
778 views

Solve spring system

I am not physics in training so if anything is unclear please request clarification. I have a set of objects to be placed on a line, linked with springs of known lengths (L) and stiffnesses (K). I ...
3
votes
1answer
5k views

Two masses attached to a spring

I'm trying to understand the solution of the following problem. Two masses $m_{1}$ and $m_{2}$ slide freely in a horizontal frictionless track and are connected by a spring whose force constant is ...
3
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3answers
1k views

Why does a spring lose its energy when compressed for a long time?

Why does a spring lose a part of its energy when compressed for a long period of time? Is it because the material gets bent?
3
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2answers
4k views

Modeling a two-mass, spring, damper system

I'm trying to model a system with two masses, two springs, two dampers, and one applied force using transfer functions. I'll then be inputting it into Simulink. The system looks like this but there ...
3
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2answers
543 views

Equal mass on either end of a spring

I'm taking physics this term and this is the first time taking physics in 3 years. Here is my homework question (of course those variables all have values but we'll use variables for now): Consider ...
3
votes
2answers
491 views

Dynamics of a Vertical Mass-Spring Simple Harmonic Oscillator with Gravity

I am having some trouble obtaining the elastic potential energy and gravitational potential energy of a simple mass spring system. In this experiment, masses attached to a spring were dropped from a ...
3
votes
3answers
260 views

What is the mathematical justification for the quadratic approximation to the energy of a spring in a one-dimensional lattice?

It follows easily from this draw, the length $l$ of this spring as a function of the vertical distance $x$, as $l(x)=\sqrt{1+x^{2}}$ Now, $l$ can be expressed as a MacLaurin expansion: $$l(x) = ...
3
votes
1answer
284 views

Simulating quantum network of harmonic oscillators

Let's say that I have a system of $n$ particles $p_1,\ldots,p_n\in\mathbb{R}^3$ (where $n$ here is on the order of 10,000). Furthermore, suppose we have a graph $G=(V,E)$ describing some network, ...
3
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2answers
2k views

How to determine viscous dampening coefficient of spring?

I'm trying to determine the viscous dampening coefficient of a spring $c$. Read about it on Wikipedia here. The two equations which I have are: $f=-cv$ and $ma+cv = -kx$ I know the spring constant ...
3
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0answers
148 views

Practice AP Physics B Exam Question regarding Momentum

I am trying to review momentum for the AP exam coming up. I will be taking the AP Physics C exam for Mechanics, but I was just practicing on any free response questions I could find and I came across ...
3
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0answers
745 views

Effective mass in Spring-with-mass/mass system

Suppose you have a particle of mass $m$ fixed to a spring of mass $m_0$ that, in turn, is fixed to some wall. I'm trying to calculate the effective mass $m'$ that appears in the law of motion of the ...
2
votes
1answer
269 views

Hooke's law doesn't work well with my spring?

I'm trying to make an application for Hooke's law using a spring, but the law doesn't give any correct result with my spring, because when I hang a $100\,\mathrm{g}$ object on the spring it's ...
2
votes
2answers
139 views

Is mass proportional to the displacement from equilibrium in Hooke's law?

If I look at Hooke's law as it's defined in my textbook, it looks like: $F = -k\Delta s$ Therefore, the restoring force of an ideal spring will be proportional to the displacement from equilibrium, ...
2
votes
2answers
130 views

Undamped oscillations. Why is the solution a linear combination of $\sin()$ and $\cos()$?

$ma = mg - cx$, where $x(0) = x_0 = 0$ is the position in which there is no tension in the rope. $dx/dt = v_0$ for $t = 0$; $v_0$ is a known constant. The discriminant of the characteristic ...
2
votes
1answer
281 views

What is the two dimensional equivalent of a spring?

I'm trying to model isotropic linear elastic deformation in two dimensions. In one dimension, I know that a linear elastic material can be thought of as a spring which obeys Hooke's law $F=-k\Delta ...
2
votes
1answer
692 views

How do I account for the direction of friction acting on a spring?

I would like to set up the equations of motion for a simple spring oscillator. Let's have a spring lying horizontally; we attach a small mass $m$ to the (massless) spring. The force of the spring ...
2
votes
1answer
192 views

Does a slinky hanging downward double in length if gravity doubles?

Also would a spring under tension greater than the force of gravity pulling the spring downward shrink in both directions until it has depleted it's stored energy while in free fall?
2
votes
3answers
534 views

Where does the loss in gravitational energy of the load go when a spring is pulled?

A mass spring system is in equilibrium. If I pull on the load by $x$ meters, the energy stored in the spring is (this is what is given in my book): $$E=\frac12kx^2 $$ However, doesn't the load lose ...
2
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3answers
430 views

Why doesn't Lenz's law predict the behavior of a rod on springs in a magnetic field?

This comes from one of the free response questions from the AP Physics B 2014 exam. 5. (15 points) A conducting rod of mass $m$ and length $L$ hangs at rest from two identical conducting ...
2
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2answers
147 views

Stick and slip motion: mass and spring inside a box model

I am trying to determine a set of differential equation which can describe the motion of a mechanical system as below. Here, at the bottom we have a plate, and a box on top of it. Inside the box, ...
2
votes
4answers
93 views

The motion of a spring

I have a question about the force set by this spring, I saw many times that $\overrightarrow{F}=-Kx\overrightarrow{i}$. I'm asking why not using $\overrightarrow{F}=Kx\overrightarrow{i}$ without the ...
2
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1answer
179 views

rate of change of spring potential energy $\frac{dU}{dt}$

Suppose we have a setup like this. In orange are two wooden sticks sort of things, and they are attached to the block of mass $m$(as usual) at a joint which is hinge type something. A similar ...
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3answers
1k views

Spring-mass system with two springs and three masses [closed]

I'm trying to solve a system of springs and masses that is confusing me. First, the balls are all lined up linearly. Secondly, the ball in the middle has a smaller mass $m$ while the first and last ...
2
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2answers
339 views

Why do joined massless springs, act like a rope under tension?

In an oscillations exercise there is a spring attached to another spring, attached to a block. Long story short: I have to find the global $k$. In the solutions it says: "Because the springs are ...
2
votes
1answer
154 views

Could someone explain to me why this is sometimes right and sometimes not?

I do not remember when, but a while a ago I was told that for a spring with stiffness $k$ and a mass $m$, the equation $-kx = ma$ never holds. (assume a horizontal spring) So if I was given a problem ...
2
votes
2answers
183 views

In continuum mechanics, what is work potential in the context of total potential energy?

I'm reading a book on the finite element method. Specifically I'm looking at the background material where they are discussing potential energy, equilibrium, and the Rayleigh–Ritz method. The book ...