# Tagged Questions

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.

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### Physics behind this drunken ball

I am trying to understand the physics behind this drunken ball: There is a wight inside the ball as he mentions, but where, at what position ? ...
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### Speed, weight and force [closed]

If a road roller of weight $W$ is rolling on the road at the speed of $X\,\mathrm{kmph}$, how much force does it apply on the surface of the road (considering a sampled surface of the same size as ...
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### How is a strength of a pull spread across two springs?

I started thinking about it when I came up with a puzzle which is probably way too elementary for this site, but it is hard for me to understand clearly. I just bought this small scale thing and I ...
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### Object Pushed by Multiple Forces [duplicate]

If we have a general object and we have multiple forces acting on it at several points. Assuming we know the center of mass, mass and moment of inertia of the object: Will the object rotate only ...
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### STEP problem (2004 paper II, mechanics)

This question says that the force exerted on a train (by its engine) when it is moving with velocity $v$ is $Pv^{\frac{3}{2}}$ where $P$ is a constant; and at velocity $v$ the resistance is $kv$ where ...
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### How do we find the cone angles of the conic sections that are the Newtonian orbits?

In planetary motion, when the eccentricity of a conic section and its semi-latus rectum are known, how do we find out the cone's semi-vertical angle and angle of cutting of the cone by plane?
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### Rain falling into a cart on an incline [closed]

I have a practise question in which a cart on and incline of angle $\alpha$ and starts initially at velocity $v_ 0$. Just as the cart moves off it starts raining vertically and the mass of the rain ...
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### What theories or formulas are involved with velocity

What theories or formulas are involved or can be added as background information in an experiment that sees a small toy car roll freely down an incline where the surface area is altered to cause more ...
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### Lack of rigour in usual derivation of Work-Energy Theorem

The derivation of the Work-Energy theorem usually goes as follows: You define the work done on a particle under net force $\vec{F}$ as $$W=\int\limits_C \vec{F}\cdot\mathrm{d}\vec{r}$$ And then you ...
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### Why does the period/frequency of a fan slow down significantly when I taped a piece of rubber band to it?

All of this was done with a standing fan set horizontally on a table. During an experiment, I had to tape a piece of rubber band to one of the standing fan's blade and measured the period of the fan. ...
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### How does $p=fv$ hold when $v=0$ and an engine is working?

Standard high school equations: Work = Force x Distance Power = Work / Time = Force x Distance / Time = Force x Velocity When a space rocket takes ...
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### Approximating energy loss caused by drag force

We know the usual aerodynamic drag equation is given by: $$F_d = -bv^2$$ Where $b$ here is just some constants combination related to the property of the fluid and the material passing through. My ...
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### Which of the Physics textbooks would you recommend I read this quarter (Analytical Mechanics)? [duplicate]

My Analytical Mechanics class this quarter has one required textbook: "Classical Dynamics of Particles and Systems" by Thornton & Marion and three recommended readings: "Mechanics" by Landau ...
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### Simple question relating to physics prac reports

I am writing a physics practical report relating to the elasticity of materials relating to their momentum in a collision. I have values for the elasticities that are all within 2% of each other but I ...
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### What are the tidal effects of Io on Jupiter?

I recall reading an essay by Asimov (I think) around 1980 stating that the tides are a function of a power of the diameter of the primary, so (surprisingly) small close moons of Jupiter raise large ...
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### Is a rope wave a perfectly transverse wave?

When i create a disturbance in a rope.What is happening at the particle level.I imagine the particles and the forces on the particles like this: According to my model there should be some ...
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### Newton's Second Law And Horse Racing

I'm a big racing fan and decided that I'd like to develop a better understanding of how weight impacts a horses performance. I did some searching on the internet and came across this article: The ...
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### Statics: Cable with distributed loads. What am I doing wrong?

This is the problem: It says: If the maximum value for the ABCD cable's tension is 15 kN, determine: a) $h_b$ b) $h_c$ My development was: 1) Whole body (ABCD). Sum of momentums in D equals ...
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### Tensions in a rope [duplicate]

If two tensions are acting on a rope such that they are equal (each is 10 N) and opposite (180 degrees) then what will be the total tension in the rope? I cant seem to figure out if these two will ...
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### Does air density influence a football player's ability to “bend” the ball?

Whilst reading an article on nasa.gov, there was a claim that I found interesting: At higher altitudes, the density r is lower producing a larger radius of curvature and a straighter path. The ...
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### Can we theoretically balance a perfectly symmetrical pencil on its one-atom tip?

I was asked by an undergrad student about this question. I think if we were to take away air molecules around the pencil and cool it to absolute zero, that pencil would theoretically balance. Am I ...
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### Simple pendulum cartesian coordinates

I'm reading Vibrations and Waves from French. I don't understand the following approximation when considering the simple pendulum: Referring to the last figure if the angle $\theta$ is small we ...
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### The applied and friction forces of a particle along a straight wire in horizontal plane

A particle of mass $14~\text{kg}$, slides along a straight wire in a horizontal plane. The coefficient of dynamic friction $\mu_k = 0.6$ The equation of the line of the wire is $y = \sqrt{3}x$ so ...
I was told forces can depend on time, location and velocity, but never on acceleration. At first I thought this must be wrong, thinking of $F=m\cdot a$. But I think/hope I now got what was meant, what ...