Newton Definition and 527 Threads

Dear all, I'm taking a second look at the Newtonian limit of GR and the covariance group. My main interest is to see how the Newton potential transforms under the covariance group of Newtonian gravity. I know that the gradient of the potential is given by the Christoffel symbol \Gamma^i_{00}...

Could someone please describe the recent LIGO project, gravitational waves and their detection in simple terms. PLEASE.

What is the underlying feature of general relativity that, unlike Newtonian mechanics, results in the correct calculation of orbits i.e. including precession (e.g. Mercury). I not asking for the mathematics (i.e. the additional term in the equation) but rather what underlying "physical"...

Homework Statement This is not a specific problem, I was just wondering, what unbalanced force acts on your body when you are in a car traveling at a constant velocity and the car comes to a sudden stop? This has to do with Newton's First Law, but I'm unsure of what force applied to your body...

If you haven't seen this video before then go watch it :D Question: Answer: It is pretty hard to imagine it as a spring and here is why: 1) At (o) the spring should move by its inertia not by any force. If we look at the planet we can summarize that there are 2 points (As I think) that could...

Hello community, Can someone direct me to good video intuitive explanation with math for first principles understanding of Quasi-Newton methods. your assistance would be most valuable. thanks

Hi, I'm looking for the real solutions to the system \begin{array}{rcl} 1 & = & v_1+v_2+v_3+v_4+v_5 \\ 1 & = & v_1^2+v_2^2+v_3^2+v_4^2+v_5^2 \end{array} Background: I'm looking at a Newton's cradle with 5 balls, each of mass ##m=1##. The first ball is pulled away and let go such that it hits...

Hey, all. I've been studying Newton's Laws and I can't help but to feel a bit uneasy as I inspect them. From my point of view, they seem to be tautological. I'll refer to Newton's First Law as N1L, and similarly for the other two Right off the bat, I suppose I don't see any reason for N1L to...

I want to make a Newton Cradle. Just wondering how I can reduce the loss of energy so the balls keep bumping for a long time

Say a lever is tilted on a fulcrum with an object on the side in contact with the floor, a mass falls onto the other side, causing the object to go flying. Does this demonstrate Action-reaction ? (action on the lever to action on the object)

These buckets are being suspended. The cords have no mass and each bucket is 3.5 kg. a.) Find the tension in the upper cord (T1) and the lower cord (T2) b.) If the apparatus is pulled upwards from the top of the upper cord, what are the new tensions of each cord? I understand the...

Homework Statement An object of mass m is allowed to slide down a frictionless ramp of angle Θ, and its speed at the bottom is recorded as v. If this same process was followed on a planet with twice the gravitational acceleration as Earth, what would be its final speed? Multiple Choice...

Homework Statement Hi, I've been tasked with showing that the length of vector F_gravity is inversely proportional with radius squared (i.e. |F_vector|=c/r^2) and is central, i.e. consistently directed toward the same point. Apparently, this is the same as (<=>) the acceleration of a particle...

Homework Statement An observer on the ground sees a person on a train just leaving the station in the east direction. explain how the observer on the ground could see the person moving to the west while the train is moving east Homework EquationsThe Attempt at a Solution At first I thought...

Homework Statement Find the extremizing (maximum) value of the function f(x) = sin x / x using Newton's 1D method. Homework Equations [/B]The Attempt at a Solution I know the maximum point in this equation is (0, 1). When I differentiated the equation twice and used the formula above, I...

Hello, I am new in the field of FORTRAN. I started to write a code using Newton Raphson method. Below is the code of main program portion only. During my calculation, I have found that my results are not converging, Any help or advice will be highly appreciated in this case. Thank you for the...

Homework Statement A tugboat pulls two barges down the river. The barge connected to the tugboat, carrying coal, has an inertia of 2.2 × 105 kg, and the other barge, carrying pig iron, has an inertia of 3.5 × 105 kg.The resistive force between the coal barge and the water is 8.0 × 103 N, and...

Homework Statement Find a double root of the equation ## f(x)= x^3+15.87x+24.34 ## correct to 3 decimal places. Homework Equations By Newton Raphson's Formula, ## x_{n+1}=x_n + \frac{f(x_n)}{f'(x_n)} ## ##f'(x)=3x^2+15.87 ## The Attempt at a Solution Does a double root means to find two roots...

Hi. Force was introduced to me as "what a force meter in an inertial frame measures". I'm a bit confused about the interpretation of Newton's second law$$F=\frac{dp}{dt}\enspace.$$ Is it a definition? Is it an empirical finding? Can it be derived theoretically? Or do we need to make the...

I have been preparing for a 9 Th grade talent exam and i can get my head around this problem I keep getting the same answer 5, i used fbd The answer is 7 ; help me out where am i wrong

Hi guys, I'm an arts undergrad student with very little knowledge of the sort of physics I'm about to ask. I was wondering if there is a calculation to work out the differentiation between running at a particular speed say 10mph against wind coming towards you at 15mph. As well as it being on...

I am trying to explain why a small object falling from a short distance on another object does not have the same impact as a bigger object falling from the same height on another object by using Newton's 2nd Law but I get stuck all the time. Can somebody please help me?

Homework Statement Calculate how much force you would have to apply to the crate to get it to go at constant speed up a 30 degree ramp. Homework Equations Using kinetic friction for equation. The Attempt at a Solution I couldn't find the formula for kinetic friction which also includes...

Homework Statement Muscle can be torn apart by a force of 100,000 N applied across an area of 1 m2. A 10 cm2 muscle therefore will be torn by a force of 100 N. If a student of average size were being lowered into a black hole of 1 solar mass, at about what distance from the hole's center will...

I recently read a paper titled : " The Saros cycle: obtaining eclipse periodicity from Newton's laws " My question is, more or less: " Is it possible to obtain an approximation of G by observing Saros periodicity ? " I'm currently studying the derivations of the Lunar , Solar, and Stellar...

Euler mentions in his preface of the book "Foundations of Differential Calculus" (Translated version of Blanton): I don't understand here, who/who all had invented/discovered the study-of-ultimate ratio (differential calculus) for rational functions long before (Newton and Leibniz), without...

1. Homework Statement I was wondering if my phi angle was in the right position from the picture. Also, it is correct that my normal force FN is perpendicular to the surface?Homework Equations Newton's second law fk=ukFN[/B]The Attempt at a Solution Refer to picture[/B]

Homework Statement Homework Equations Newton's 2nd Law The Attempt at a Solution I was wondering if anyone could verify that I have all the correct vectors or if I am missing any. I just wanted to check before I started trying to derive the equations. [/B]

Homework Statement Homework Equations F=ma ac=v^2/r f=uN v=v0+at w=v/r The Attempt at a Solution v=v0+at v=vo+umv^2/r v^2(u/r)-v+vo=0 I don't see what differential equation i could use since the speed is dependent on the friction (equal to friction coeff times centripetal force) which in...

Hello everyone! I'm a freshman intended physics major at UC Berkeley, and I am taking the honors mechanics course. It is really rigorous, but I do feel like I'm learning a lot. My strengths are Newton's Laws-based questions, and my current weakness is setting up differentials. I love...

I've searched a little bit and found that I can derive kepler's third law from Newton's law of gravitation. That's okay. But I want to deduce kepler's second law too: "An imaginary line joining a planet and the sun sweeps out an equal area of space in equal amounts of time". I know it's possible...

Greg Bernhardt submitted a new PF Insights post The Isaac Newton Quiz Continue reading the Original PF Insights Post.

I've been wondering if space as understood by Newton, as an actual thing that contains matter, is relevant to modern physics. Has Newton's idea been disregarded? Is Aristotle's view that there is no space-vacuum now accepted? Thanks

Hi guys, I have been searching for references that could tell what are the average limits of impact (in Newtons per example) of running activity into human´s feet (material = bone). Basically the question I am trying to answer is per example to understand how much of linear acceleration...

i was wondering, instead of thinking the apple was pulled down by some force to Earth , why didn't he think that there was a force pushed the apple down from above? , imagine when you leave in that particular year when he was alive.

How did Kepler derive his laws of Planetary Motion without knowing about Newton's law of gravitation? Specifically, the first law of planetary motion which says that planets follow elliptical paths - how did he figure that out without the knowledge of the gravitational pull of the sun? Was it...

Do you think Newton's piety was important to developing or fueling his philosophical and psychological impulses to be a great scientist and mathematician ? Did his religious and alchemical goals orient his scientific researches; his outstanding mechanical, mathematical, and optical theories...

I was reading the Wikipedia page on Dynamism in order to get an idea of the motivation and thinking behind Liebniz's physics. In it there is this paragraph: In the opening paragraph of Specimen dynamicum (1692), Leibniz begins by clarifying his intention to supersede the Cartesian account of...

Hi, so I learned the definition of a Newton which is Definition of Newton - 1 Newton is the force needed to accelerate 1 kilogram of mass at the rate of 1 metre per second squared. - 1N = kg*(m/s^2) But I'm very curious about one thing What tools did he use, and how could Newton...

We all know that f = m*a. But why can't we write this as f = m * s/t^2 ? I know this is wrong. But what is the reason?? Need opinion on this. Thankyou.

First of all, I am sorry if this is in the wrong subforum; I'm not sure if astrodynamics should be under astronomy. The post is also fairly long. My problem is that in my derivation of the center of mass of a binary system, I get a conflicting result for the distances of the center of mass to...

To summarize, I am doing some drop test by hanging an object off of a fork lift forks, raising it, dropping it onto either concrete floor or some foam/dampening material. an accelerometer is placed on the object being dropped (epoxied on). if i am getting 46403.666 Newtons as the force, how...

Dear Physics Forum, I really don't understand the concept of watt and Newton. I have two questions, perhaps someone can explain it to me. ======================================================= Case 1: If a one Newton force is applied to a one kg rocket in space with no or very little effect of...

I need to think of all the physics principles to explain how one can stack spherical items (ex. baseballs) on top of each other. So far I've thought of one. 1. Newton's third law In this case, the reaction is the normal force in each baseball that is stacked and the action is the force of...

how can i find this book?? ( Isaac Newton - The Mathematical Principles of Natural Philosophy)

I understand that this has been answered, but I can't follow it. My apologies, physics is a realm I want to understand but it doesn't come naturally and I have no High school physics background just 1st yr Engineering physics. (passed with supps.) A particle is projected vertically upward in a...

Homework Statement Derive Newton's and Lagrange's equation of motion for the system. Discuss differences and show how Newton's equations can be reduced to lagrange's equations. Assume arbitrarily large θ. The system is a pendulum consisting of a massless rod of length L with a mass m...

Alright, I've been looking everywhere, and tried to use a few formulas but they don't answer what I'm trying to find. Let's say I have a car that weighs 1815kg )4000 pounds) and its traveling at 90kph (roughly 56 mph) with a flat one square meter (10.76 sq ft.) grill facing the wind as it...

Who was greater (in your opinion), Einstein or Newton? and Why?

Homework Statement A 91-kg astronaut floats outside a 3,131 kg spacecraft . She's initially stationary with respect to the spacecraft . Then she pushes against the spacecraft , and moves away at 0.195 m/s to the left. Find the SPEED of the recoiling spacecraft . Homework Equations Force =...