What is Newtonian physics: Definition and 39 Discussions
Classical mechanics is a physical theory describing the motion of macroscopic objects, from projectiles to parts of machinery, and astronomical objects, such as spacecraft, planets, stars, and galaxies. For objects governed by classical mechanics, if the present state is known, it is possible to predict how it will move in the future (determinism), and how it has moved in the past (reversibility).
The earliest development of classical mechanics is often referred to as Newtonian mechanics. It consists of the physical concepts based on foundational works of Sir Isaac Newton, and the mathematical methods invented by Gottfried Wilhelm Leibniz, Joseph-Louis Lagrange, Leonhard Euler, and other contemporaries, in the 17th century to describe the motion of bodies under the influence of a system of forces. Later, more abstract methods were developed, leading to the reformulations of classical mechanics known as Lagrangian mechanics and Hamiltonian mechanics. These advances, made predominantly in the 18th and 19th centuries, extend substantially beyond earlier works, particularly through their use of analytical mechanics. They are, with some modification, also used in all areas of modern physics.
Classical mechanics provides extremely accurate results when studying large objects that are not extremely massive and speeds not approaching the speed of light. When the objects being examined have about the size of an atom diameter, it becomes necessary to introduce the other major sub-field of mechanics: quantum mechanics. To describe velocities that are not small compared to the speed of light, special relativity is needed. In cases where objects become extremely massive, general relativity becomes applicable. However, a number of modern sources do include relativistic mechanics in classical physics, which in their view represents classical mechanics in its most developed and accurate form.
Paul Gregg - BSME 1980 UofUtah
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I want to find a dimensionless value that differentiates between concentrated mass systems such as the solar system and dispersed mass systems such as a galaxy. I assume spherical and radial symmetry, consider both the cases for point masses or smooth mass distributions.
The only value I can...
https://www.feynmanlectures.caltech.edu/I_10.html
(From the paragraphs after equation 10.5)
'It is not just a definition to say the masses are equal when the velocities are equal, because to say the masses are equal is to imply the mathematical laws of equality, which in turn makes a prediction...
Let's say a small object orbits around massive object at some distance in perfectly circular orbit. In Newtonian physics the force acted upon orbiting body is:
Force = m1 * orbital_speed^2 / distance = G * (m1*m2) / r^2
for an object of 1kg orbiting a body of 2*30^kg at the distance of 1.521 *...
The answer is tD = [D_0 - 3/4ct - 1/2ct] I just have 2 questions.
I realize for 2 vectors approaching it is negative for distance and for velocity positive. What be the rule for time? How do I find vector answers for velocity and distance and time?
I am confused why I have "td = ..." ? Can...
At first I tried solving the problemteh following way:
Due to symmetry let the rods connected to the green rod have tension forces in magnitde T1 => mg = 2T1cos(a), where a is half the angle formed by the two rods. From tere I got an expression from the longer rods in the force projected by them...
I have been trying out with this one for a long time with no luck getting the exact expression. I am pretty sure this is somehow related to Kepler's third law but unable to establish the connection and the integrals I get from energy conservation yield different results. Any ideas?
I'm a man. The only thing that I think distinguishes me from the rest is that I am in love with the truth. The truth is very beautiful, that's why I pursue her and when I find her I do nothing but praise her beauty, I love her, I adore her and I am faithful to her. And she, in love with me...
I know that I have to calculate force that is generated by water. However, I do it wrong way.
## A = \pi r^2 ##
## v = \frac Q A = \frac Q {\pi r^2}##
## F = P t = mvt = ...? ## - have problem with mass. and is it even correct way?
if I can calculate F - its easy afterwards...
##\tau = F l ##...
What exactly is this equation telling me? How can I use it to work out the Equations of Motion given an equation of potential energy? Won't I have to solve a PDE? I'm extremely sorry if this question comes off ignorant.
Hi,
I am having trouble understanding the intuition behind the problem I attached.
Work is the product of the force and displacement in the direction of displacement, so since the crate is moving horizontally from A to B why isn't the displacement AB = 6m?
Thanks in advance
Newtonian Physics states in part that 'every object has an absolute state of motion relative to absolute space, so that an object must be either in a state of absolute rest, or moving at some absolute speed.'
Granting that if absolute space were to exist, we have no means to measure it at...
In GR Mass is said to curve spacetime which is the explanation for Gravity versus Newtonian physics where it is explained as all matter attracts each other. My question is how does curved spacetime cause objects traveling at different velocities to follow different paths? If gravity was only due...
I have several questions about the Newtonian equation for Gravity Gm1m2/r^2. First, I want to point out this equation is only valid for point masses or when the two objects are sufficiently far apart.This is because the r squared term on bottom means that the relationship between force and...
What types of objects does Newtonian mechanics deal with? Is it just rigid bodies? I’m not sure how Newton’s laws could explain something like the motion of a wiggling rope.
In a closed system, I know the rider wouldn't be able to change the combined center of gravity of the system by moving his weight around. If he pushes the bike to lean to the right, he would go to the left by the amount that would keep the combined cog the same.
But a bike with tires and a road...
Hello All,
I have a question for which I'd like an authoritative answer, if some physics genius would be so kind. I'll try to provide as much background as I can but follow up questions for clarity are more than welcome!
So I'm working on the design for a patent application and it involves a...
Homework Statement
truck moves at 22,5 m/s
On board the truck, behind, is a box.
the static friction coefficient for the box, is 0,250 with regard to the friction between truck floor and the box floor.
calculate the shortest possible stopping distance, such that the box does not slide at...
Homework Statement
Hello,
Regarding the idea of Newtonian force pairs, imagine a bottle resting on a table:
Weight force exerted on bottle by Earth and normal contact force on bottle by table are not Newtonian force pairs because they are different types and act on the same object.
Weight force...
Hi everyone.
Thanks for attempting the audacious challenge of deciphering the undistilled chaos that is this thread. I'd appreciate any efforts to clarify my very much flawed understanding of basic physics.
1. This is most likely a trivial question but why is the normal force perpendicular to...
Homework Statement
Just my own personal questions concerning Newtons laws.
For the most part I grasp all three laws to adequately take care of my homework, but I have some conceptual questions that keep bugging me.
when solving diagrams including net forces that are acting on an object, the...
Hey all! I was thinking about a problem the other day. (For some background, I'm a geology student - I took A-level Physics in high school, a few years ago, and have done a few physics modules since then at University, so I'm probably better educated in physics than the average person, but it's...
It's fairly common to use Lagrangian mechanics to handle arbitrary space coordinates. But is it ever actually used to handle arbitrary time coordinates, particularly in Newtonian mechanics?
For example, does anyone consider the transformation
x = X
t = T + uX
where (x,t) are normally...
i was having an argument with my friend.
He claims that acceleration for object that is lighter, let say a stone (1000kg) and ball (1kg). If we were to throw them up in the sky with the same initial speed, their acceleration would always be 9.81ms^2 (depending on sign conventions). Am i right...
Homework Statement
The problem is basically a fair ride that has a pole as its base, another pole sticking out of it, the a cable with a chair at the end. I am given the length of the rod sticking out (3.00 m), the cable (5.00 m) and the angle between 30.0\circ. I have to find the time it takes...
From what I have learned so far, it appears that a light emission orthogonal to motion acts exactly like a Newtonian massive particle with conserved longitudinal momentum. Is this correct?
If so it would seem to be a cosmic coincidence of monumental proportions.
Having given it some...
Homework Statement
A 2.0 kg block rest on a 4.0kg block that is on a frictionless horizontal table. The coefficients of friction are u_s = 0.3 and u_k = 0.2. What is the maximum force F that can be applied to the 4.0 kg block if the 2.0 kg block is not to slip? If F has half this value, find...
Hey guys,
Im trying to derive the following equation
(mc^2) [(1/E2)-(1/E1)]+cos(theta)-[((E1-E2)^2)/(2E1E2)]=1
E1 = Incident Photon's energy
E2 = Scattered Photon's energy
theta= scattering angle
m = mass of electron
c = s
Using conservation of energy,conservation of mass, and...
Homework Statement
Derive the equation non-relativistic equation for Compton scattering
(mc^2) [(1/E2)-(1/E1)]+cos(theta)-[((E1-E2)^2)/(2E1E2)]=1
E1 = Incident Photon's energy
E2 = Scattered Photon's energy
theta= scattering angle
m = mass of electron
c = s
Here is the lab
In...
Before I begin, let me say this is my first time on this forum, and am terribly sorry if I screw something up here. Let me also say that my physics lab is ahead of my physics class, so my knowledge on angular momentum is lacking.
Also, this lab is due tomorrow. I know it's short notice, but I...
Homework Statement
Im doing a philosophy, history and politics of science subject and the question is whether gravity was waiting to be discovered or was it an intellectual construct particular to the 17th century and Newton.
Homework Equations
The Attempt at a Solution
I'm...
I wish your help in creating a tabletop Newtonian physics demo.
My friends do not believe that the centrifugal force is imaginary. They believe that, if you swing a pail of water in a circle over your head and let the rope go, the pail will sail *away* from you (as opposed to tangential to...
I read in a book that relativity and Newtonian physics don't work with each other or something like that. Like when Einstein founded Relativity, Newtonian physics were partialy disregarded because Newtonian physics didn't account for relativity. Can Newtonian physics be like converted to work...
:confused: I need more help please. I am moving along slowly in my physics quest to understand. The readings are more difficult and my understanding comes in and out. Please review, see how I did (answers marked with *) and make comments to help me learn. Thanks.
1. Which of the...
Can someone help me with these questions. I am a beginner in the study of physics and would like some help. I have attempted to answer these but would like to know if I am correct and a brief (very brief) explanation. Thanks in advance for your assistance.
An object maintains its state of...