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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List of good classical physics books
What are some good books for learning the concepts of Kinematics, Newton laws, 2D Motion of Object etc.?
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Why does kinetic energy increase quadratically, not linearly, with speed?
As Wikipedia says:
[...] the kinetic energy of a non-rotating object of mass $m$ traveling at a speed $v$ is $mv^2/2$.
Why does this not increase linearly with speed? Why does it take so much ...
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8answers
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Why does the atmosphere rotate along with the earth?
I was reading somewhere about a really cheap way of travelling: using balloons to get ourselves away from the surface of the earth. The idea held that because the earth rotates, we should be able to ...
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5answers
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Confused about the role of mass
I'm far from being a physics expert and figured this would be a good place to ask a beginner question that has been confusing me for some time.
According to Galileo, two bodies of different masses, ...
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5answers
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With Newton's third law, why are things capable of moving?
I've got a rather humiliating question considering newton's third law
"If an object A exterts a force on object B, then object B exerts an equal but opposite force on object A" -> $F_1=-F_2$
...
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4answers
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Anti-gravity in an infinite lattice of point masses
Another interesting infinite lattice problem I found while watching a physics documentary.
Imagine an infinite square lattice of point masses, subject to gravity. The masses involved are all $m$ and ...
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infinite grid of planets with newtonian gravity
Assuming only Newtonian gravity, suppose that the universe consists of an infinite number of uniform planets, uniformly distributed in a two-dimensional grid infinite in both directions and not moving ...
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4answers
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Newton's Bucket
Newton's Bucket
This thought experiment is originally due to Sir Isaac Newton. We have a sphere of water floating freely in an opaque box in intergalactic space, held together by surface tension and ...
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3answers
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Galilean invariance of Lagrangian for non-relativistic free point particle?
In QFT, the Lagrangian density is explicitly constructed to be Lorentz-invariant from the beginning. However the Lagrangian
$$L = \frac{1}{2} mv^2$$
for a non-relativistic free point particle is ...
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8answers
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Why don't spinning tops fall over?
One topic which was covered in university, but which I never understood, is how a spinning top "magically" resists the force of gravity. The conservation of energy explanations make sense, but I don't ...
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4answers
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Logical connection of Newton's Third Law to the first two
The first law and second laws of motion are obviously connected. But it seems to me that the third law is not related to the first two, at least logically.
(In Kleppner's Mechanics the author states ...
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1answer
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Kepler problem in time: how do two gravitationally attracting particles move?
Two particles with initial positions and velocities $r_1,v_1$ and $r_2,v_2$ are interacting by the inverse square law (with G=1), so that
$$ {d^2r_1\over dt^2} = - { m_2(r_1-r_2)\over |r_1-r_2|^3} $$
...
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Why is there a $\frac 1 2$ in $\frac 1 2 mv^2$?
For elastic collisions of n particles, we know that momentum in the three orthogonal directions are independently conserved:$$ \frac{d}{dt}\sum\limits_i^n m_iv_{ij} =0,\quad j=1,2,3$$
From this, it ...
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2answers
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Why I think tension should be twice the force in a tug of war
I'm going to provide my argument for why I think the tension in a rope should be twice the force exerted on either side of it.
First, let's consider a different example.
Say, there is a person named ...
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4answers
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Violation of Newton's Second Law (?)
Here the big circle denotes the circular path of a stone(small circle on path) tied to a string from the centre of the circular path .
This is COMPLETELY HORIZONTAL
At an instant the velocity in ...
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1answer
534 views
Dependence of Friction on Area
Is friction really independent of area? The friction force, $f_s = \mu_s N$. The equation says that friction only depends on the normal force, which is $ N = W = mg$, and nature of sliding surface, ...
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11answers
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Why do we say that the earth moves around the sun?
In history we are taught that the Catholic Church was wrong, because the Sun does not move around the Earth, instead the Earth moves around the Sun.
But then in physics we learn that movement is ...
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4answers
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Why does a ballerina speed up when she pulls in her arms?
My friend thinks it's because she has less air resistance but I'm not sure.
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1answer
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Torque Required For a Motor to Move an Object on Wheels?
I've been attempting to calculate how much torque a motor needs to produce in order to start a stationary object on wheels moving. (The torque is being applied to the rear 2 wheels, the front 2 are on ...
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2answers
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History of interpretation of Newton's first law
Nowadays it seems to be popular among physics educators to present Newton's first law as a definition of inertial frames and/or a statement that such frames exist. This is clearly a modern overlay. ...
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6answers
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What is the difference between Newtonian and Lagrangian mechanics in a nutshell?
What is Lagrangian mechanics, and what's the difference compared to Newtonian mechanics? I'm a mathematician/computer scientist, not a physicist, so I'm kind of looking for something like the ...
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6answers
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How do you explain spinning tops to a nine year old?
Why don't spinning tops fall over? (The young scientist version)
My nine year old son asked me this very question when playing with his "Battle Strikers" set. Having studied Physics myself, I am very ...
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5answers
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Is the energy conserved in a moving frame of reference?
Consider this situation:
When the box is at the bottom of the frictionless incline, it will have a velocity of $v_f$. The person is an inertial frame of reference that moves at a constant ...
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2answers
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How does Newtonian mechanics explain why orbiting objects do not fall to the object they are orbiting?
The force of gravity is constantly being applied to an orbiting object. And therefore the object is constantly accelerating. Why doesn't gravity eventually "win" over the object's momentum, like a ...
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1answer
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How does Newton's 2nd law correspond to GR in the weak field limit?
I can only perform the demonstration from the much simpler $E = mc^2$.
Take as given the Einstein field equation:
$G_{\mu\nu} = 8 \pi \, T_{\mu\nu}$
... can it be proved that Newton's formulation ...
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2answers
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Path to obtain the shortest traveling time
Asume we have a particle sitting at the point A(0,0) in a gravitational field.
(g=9.81) It is going to move along some path to the point B(a,b) Where a>0 and b<0.
What is the curve the particle ...
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2answers
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Does a ski racer with a larger mass have an advantage?
Does a ski racer with a greater mass have an advantage over a racer with a lesser mass?
If mass of one racer is 54 kg and the mass of a more slender racer is 44 kg I know the speed at which they ...
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2answers
503 views
What will be the relative speed of the fly? [duplicate]
It has happened many times and i have ignored it everytime.
Yesterday it happened again .
I was travelling in a train and saw a fly (insect) flying near my seat.
Train was running at a speed of ...
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10answers
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How did Newton discover his second law?
I've always assumed/been told that Newton's 2nd law is an empirical law — it must be discovered by experiment. If this is the case, what experiments did Newton do to discover this? Is it related to ...
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2answers
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Is there an intuitive reason the brachistochrone and the tautochrone are the same curve?
The brachistochrone problem asks what shape a hill should be so a ball slides down in the least time. The tautochrone problem asks what shape yields an oscillation frequency that is independent of ...
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3answers
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Where does the reaction to action come from?
Third Newton's law, $F_{1->2} = -F_{2->1}$
So, how does a body react with the same force that it's receiving from the acting body? Is it the electric interactions at the subatomic level? When ...
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Does leaning (banking) help cause turning on a bicycle?
I think it's clear enough that if you turn your bicycle's steering wheel left, while moving, and you don't lean left, the bike will fall over (to the right) as you turn. I figure this is because the ...
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3answers
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Is gecko-like friction Coulombic? What is the highest known Coulombic $\mu_s$ for any combination of surfaces?
Materials with large coefficients of static friction would be cool and useful. Rubber on rough surfaces typically has $\mu_s\sim1-2$. When people talk about examples with very high friction, often ...
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Why does the cart move? [duplicate]
A while ago someone proposed the following thought experiment to me:
A horse attached to a cart is resting on a horizontal road. If the horse attempts to move by pulling the cart, according to the ...
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4answers
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Is acceleration an absolute quantity?
I would like to know if acceleration is an absolute quantity, and if so why?
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1answer
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Analyzing the motion of a ball rolling without slipping inside a hemispherical bowl
Consider a solid ball of radius $r$ and mass $m$ rolling without slipping in a hemispherical bowl of radius $R$ (simple back and forth motion). Now, I assume the oscillations are small and so the ...
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Newton's second law of motion in terms of momentum
I am reading a document and in answer to the question State Newton’s second law of motion the candidate answers that The force acting on an object equals the rate of change of momentum of the object. ...
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2answers
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The angle of launching an Angry Bird that will land the bird furthest from the launching point is 45 degrees?
This is a question motivated by Angry Birds.
When playing the game, I notice that if the initial velocity is constant, the way to land a bird furthest away from the launching point is by launching ...
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1answer
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Coriolis force in free fall
Does the coriolis force has any measurable effect in free fall from large heights?
Take for example the sky diving experiment by F. Baumgartner who started from a height of about 40 km above New ...
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1answer
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A Question about Virtual Work related to Newton's Third Law
In describing D'Alembert's principle, the lecture note I was provided with states that the total force $\mathbb F_l$ acting on a particle can be taken as,
$$\mathbb F_l=F_l+\sum_mf_{ml}+C_l,$$
...
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1answer
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How to modify the bullet trajectory based on the ballistic coefficient?
I am new to the physics surrounding bullet trajectory and how it is calculated. I am a software developer and I am working on a ballistics calculator for rifles. I am using wiki for the trajectory ...
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2answers
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Foucault pendulum
The equations of motions for a Foucault pendulum are given by:
$$\ddot{x} = 2\omega \sin\lambda \dot{y} - \frac{g}{L}x,$$
$$\ddot{y} = -2\omega \sin\lambda \dot{x} - \frac{g}{L}y.$$
What are the ...
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4answers
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How long must escape velocity be maintained?
Escape velocity from Earth's surface is 11.2 Kilometres/second
How long would one need to maintain this escape velocity to actually escape Earth's gravitational pull? Must this 11.2 km/s velocity ...
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9answers
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What is the difference between weight and mass?
My science teacher is always saying the words "weight of an object" and "mass of an object," but then my physics book (that I read on my own) tells me completely different definitions from the way ...
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10answers
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Is the distance between the sun and the earth increasing?
M = mass of the sun
m = mass of the earth
r = distance between the earth and the sun
The sun is converting mass into energy by nuclear fusion.
$F = \frac{GMm}{r^2} = \frac{mv^2}{r} \rightarrow r ...
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Explanation that air drag is proportional to speed or square speed?
A falling object with no initial velocity with mass $m$ is influenced by a gravitational force $g$ and the drag (air resistance) which is proportional to the object's speed. By Newton´s laws this can ...
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2answers
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Does constraint for speed of Electric and magnetic fields violates Conservation of momentum or Newton's third law?
I'm just a beginner so bear with me. Consider two frames at rest wrt to each other separated by distance enough for light to take a minute or so. At a given instant we create two large dipoles by some ...
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The Double Integrator: Matching velocity and position as quickly as possible with only a limited amount of force available
If a body with mass $m$ begins at position $x_0$ with velocity $v_0$ and experiences a force that varies as a function of time $f(t)$ (and we ignore gravity, friction, and everything else that might ...
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1answer
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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 ...
2
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1answer
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Explanation of a Foucault pendulum
The equations of motion of a Foucault pendulum is given by:
$$\ddot{x} = 2\omega \sin\lambda \dot{y} - \frac{g}{L}x$$
$$\ddot{y} = -2\omega \sin\lambda \dot{x} - \frac{g}{L}y$$
where $\omega$ is ...
