Questions tagged [spring]

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

1413 questions
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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.
40
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6 answers

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 professor gave a practice problem in which a spring of…
nhinkle
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Why does my bumper scrape when driving fast over a bump but not slow?

When driving my car over a bump or a quick change in gradient (from flat to uphill or downhill to flat), if I don't drive slowly and the bump/change in gradient is large enough, I'll end up with my front bumper dragging on the road/bump. But if I go…
30
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3 answers

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.
Mörre
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29
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2 answers

Why do my experimental data for Hooke’s law not match the expected data?

As we all know, force applied to a spring is directly proportional to the extension of spring as shown below: However, my experimental results for a simple spring from a school laboratory don't match this behaviour: Why is this happening? I don't…
27
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1 answer

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). For portable energy sources, fuel cells have been…
26
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8 answers

Why is the potential energy of a spring the same when it is compressed and stretched?

I'm giving a high school lecture and I want to introduce the potential energy of a spring. My students have not learned the Hooke's Law and the notion of integral is too advanced. I'm really trying to justify with a hand waving argument that the…
24
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4 answers

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?
PunkZebra
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22
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1 answer

Why does a flat sheet roll back into a cylinder when having rolled it once?

For example, if you were to roll a piece of paper into the shape of a hollow cylinder and then try to return the paper to its original, flat shape, it would naturally roll to the cylinder when you let go. Why would an originally flat surface, when…
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3 answers

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 capacitances and resistances add when they are…
19
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5 answers

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 added to the system). When forces are removed, the…
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2 answers

Can Hooke's law be derived?

Can we derive Hooke's law from the theory of elasticity? I know it is not a fundamental law and therefore can be derived from more basic considerations.
17
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4 answers

Will slinky length be different on the moon?

If we hold one end of a slinky and leave other end free, the earth's gravity applies force on the slinky and it expands. If we do the same on the moon with the same slinky, will the acquired height of the slinky be different?
15
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5 answers

Why are springs better at pulling than pushing?

We learnt that a spring stores and releases energy in either direction from the resting position when extended by some distance. When I tried doing this is real life by creating a very low friction surface and a spring and a mass, I noticed that the…
14
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4 answers

When an electron hits a fluorescent screen mounted on a spring, why can't we get both position and momentum?

From the Heisenberg's Uncertainty Principle for position and momentum we know that, $x$ and $p$ of a particle cannot be measured simultaneously with arbitrary accuracy. $$\Delta x \Delta p \geq \hbar/2 $$ How does the uncertainty principle work in…
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