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

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27
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3answers
3k views

Stretch length of horizontal and vertical springs

If the spring in Figure A is stretched a distance d, how far will the spring in Figure B stretch? The spring constants are the same. The answer is "by half". I don't get it, to me it's the same.
18
votes
5answers
60k views

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 ...
17
votes
5answers
2k views

How is potential energy actually stored in a steel spring at the atomic level?

Elasticity is one the most intriguing phenomena, wiki gives a summary explanation of what happens in a steel spring: the atomic lattice changes size and shape when forces are applied (energy is ...
13
votes
3answers
3k 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 ...
12
votes
4answers
34k 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?
12
votes
2answers
4k 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.
11
votes
1answer
2k views

Why don't they use springs as an energy source for cell phones?

I know they used springs for clocks way back in the day and now it's all lithium ion batteries. For reference, consider the Iphone that has a battery with a capacity of 5 Watt hours (18,000 joules). ...
8
votes
2answers
1k 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 ...
8
votes
4answers
3k 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 ...
8
votes
2answers
1k 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
19k 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
216 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 ...
7
votes
3answers
226 views

Center of mass of heavy spring

If a heavy spring of uniform density and mass $m$ is hung vertically so that it is stretched by gravity under its own weight, where is the center of mass? I have had a few people tell me it is 1/2 ...
7
votes
1answer
160 views

What's the hooke's law in general relativity?

Now I'm trying to derive the hooke's law in general relativity,but I have many difficulties with it. First,I try to search google/google scholar.But I found nothing about the hooke's law in general ...
6
votes
1answer
448 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 $T=2\pi\sqrt{\...
6
votes
4answers
4k 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?
6
votes
3answers
2k views

Equivalent spring-constant for infinite square grid of springs

Consider an infinite square grid, where each side of a square is a spring following Hooke's law, with spring constant $k$. What is the relation between the force and displacement between two points? ...
6
votes
2answers
340 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
4answers
10k 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 ...
5
votes
2answers
582 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, ...
5
votes
2answers
917 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
votes
3answers
347 views

Is it true that spring has more force acting on it at its positive maximum amplitude than than at the negative one?

Am I missing something? It seems obvious to me that at $+A$ and $-A$, the spring has restorative forces equal in magnitude but opposite in direction. But since gravity is always pulling it down, ...
5
votes
3answers
819 views

Is there any tension in a massless spring that connects two free falling bodies in different horizontal planes?

Two bodies A and B of same mass $m$ are attached with a massless spring and are hanging from a ceiling with a massless rope. They are in same vertical plane but not in same horizontal plane. Now the ...
5
votes
3answers
720 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
2answers
196 views

Maximum reading after dropping a mass onto a scale

If one drops an object onto a scale, the needle will temporarily spike to a high reading. Given a mass $m$ dropped from a height $h$ above a spring scale, is there a good way to approximate what the ...
5
votes
1answer
809 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
794 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: ...
5
votes
1answer
189 views

Newton's Third Law As Discussed in Den Hartog's Mechanics

A question, but some preliminaries in order to avoid answers involving concepts not yet introduced in the text I'm reading--Den Hartog's Mechanics. Near the very beginning of his book, Den Hartog ...
4
votes
1answer
3k 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
4answers
179 views

Two mass one-spring system natural frequency

Suppose I have two masses $m_1, \ m_2$ connected by one spring of stiffness $k$ through their centres of mass, lying on a frictionless surface and the system is set into oscillation. I want to find ...
4
votes
2answers
108 views

Motion of a bouncing sphere with a spring attached inside

Imagine a sphere with inside a spring attached (between opposite sides). You let it fall from a certain height, after which it bounces from a flat surface. The sphere is rigid. Will the following ...
4
votes
2answers
3k 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
2answers
1k 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 ...
4
votes
1answer
382 views

How to determine sign of coefficients in simple spring, damper, mass system?

For a system of the sort shown below: I have come to realize that I continuously make mistakes when it comes to determining the signs (or specifically the direction of the forces) of the ...
4
votes
1answer
215 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
1k 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
votes
3answers
9k 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
198 views

Imposing symmetries on asymmetrical dynamic systems

Let us say we have a one dimensional system of masses connected by springs. All the masses are equal and the springs alternate with spring constants of $k$ and $6k$. The appropriate way to analyze ...
4
votes
1answer
341 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 ...
4
votes
3answers
624 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) = 1+\...
3
votes
3answers
575 views

Spring pendulum - why is it possible to use this equation?

It is known that, when we describe the spring pendulum, we are bound to use the formula $T = 2\pi \sqrt{m/k}$, however, we can go further and set $\omega = \frac{2\pi}{T}$ I ponder why is this ...
3
votes
1answer
13k 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
votes
1answer
587 views

Springs at an angle [closed]

I'm trying to find the equation of motion for the following system: This is how I proceeded: Let's call the length of the hypotenuse $s$. Then, $$F = 2 \sin{\theta}\cdot-k(s - l_o) = -2kx \frac{...
3
votes
3answers
293 views

What is the significance of clamping the center of the spring?

7. A block is hung on a spring, and the frequency $f$ of the oscillation of the system is measured. The block, a second identical block, and the spring are carried in the Space Shuttle to space. The ...
3
votes
4answers
4k views

Is 'restoring force' a particular type of force?

I have a question about the restoring force in elastic band or rope which confusing me for a long time. As I was told in high school physics, for an elastic band (or spring), if Hooke's law holds, we ...
3
votes
2answers
7k 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
1answer
74 views

Mass dropped on a spring

I thought this would be a particularly simple problem but it is turning out to be quite the opposite. I am sure I am doing a very simple mistake. The problem statement is that there is a mass which ...
3
votes
1answer
74 views

Motion of $n$ bodies connected with springs

Let's consider $n$ cuboids moving without friction, each of mass $m_i$. Each wo neighboring cuboids are connected with a spring of the coefficient $k$. ...
3
votes
3answers
426 views

How to apply Newton's Third law when a massless spring is compressed by a moving block?

I was really confused about the applicability of Newton's Third Law in case of non-rigid bodies like springs. While googling about this I read that Newton's Third Law fails in case of springs. I saw ...
3
votes
2answers
9k 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 ...