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Newtonian mechanics covers the discussion of the movement of classical bodies under the influence of forces by making use of Newton’s three laws. For more general discussion of energy, momentum conservation etc., use classical-mechanics, for Newton’s description of gravity, use newtonian-gravity.

It seems that some outside influence abruptly stopped the wheel. So the hamster is not "messing up his footing", it is rather the hamster's continued running that launched him. It might be no coinci …
answered Jul 28 '13 by Johannes
Which scenario to chose? A) I am standing with my back against a massive granite wall. A solid block of concrete of mass 100,000 kg is approaching me with a momentum of 10,000 kg m/s. It follows that …
answered Aug 15 '14 by Johannes
An observer in the lift and an observer at rest in the building observe the same energy being transferred in heat: A clay ball with mass $m$ drops from the ceiling in an elevator and hits the floor. …
answered Dec 24 '12 by Johannes
I'd like to morph the question somewhat: what happens when a tank alternatively sucks in and expels fluid through the same nozzle? The surprising answer is: it will move in the direction it would mov …
answered Aug 15 '13 by Johannes
The point is: you can apply Newton's law $dp/dt= F = mg - T$, but you can't assume $dp/dt = m dv/dt$ as $dm/dt$ is nonzero. The fundamental law in Newtonian dynamics is the object's rate of change in …
answered Apr 12 '14 by Johannes
A year has passed since this question was posed, and as luck would have it, this week a paper appeared on the science preprint repository ArXiv discussing exactly this phenomena. The preprint (PDF) is …
answered Aug 15 '15 by Johannes
The equation $E=mc^2$ equates rest energy to mass. There is a third symbol in this equation that represents the speed of light, but this is a universal constant. One can always select physical units s …
answered Dec 22 '12 by Johannes
Ok, I am a layperson when it comes to human physiology (and so are the vast majority - if not all - members of Physics SE), but with that disclaimer, I am going to attempt answering your question. W …
answered Oct 30 '11 by Johannes
All basic laws of physics are frame-independent. They either exhibit Galilean (non-relativistic) or Lorentzian (relativistic) invariance. Examples are Newton's laws (Galilean), Maxwell's equations (Lo …
answered Dec 23 '12 by Johannes
Some rough figures: earth's mass is about $6 10^{24}$ kg. The mass of the total world population is roughly 7 billion times 80 kg or about $6 10^{11}$ kg. So earth is 13 orders of magnitude (10 trilli …
answered Jul 11 '13 by Johannes
Think about it like this: in order to get all lengths (i.e. your own length as well as the height of your jump) to scale down by a factor $\alpha$, while keeping the contraction velocity of your muscl …
answered May 30 '13 by Johannes
Your starting point "normal methods of acceleration [..] add [..] constant energy over time to an object" is not correct. A constant force I would classify as "a normal method of acceleration". Such …
answered Jul 21 '13 by Johannes
How many hamsters do you need to power a 15 W light bulb? I am going to treat this as a Fermi problem. Let's give a hamster a typical mass $m$ of $\ 0.15\ kg$. And let's assume this hamster can climb …
answered Aug 2 '13 by Johannes
The frequency of a simple pendulum is easy to compute, even for large angular amplitudes. Consider the pendulum in the figure below. For small amplitudes ($2l-d << l$) this pendulum oscillates at ang …
answered Nov 3 '18 by Johannes
I feel tempted to give a bit of a twist to this question. As John Rennie mentions in a comment above, unless you are talking about slowly moving microscopic projectiles, drag forces are best modeled a …
answered Jan 26 '13 by Johannes

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