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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Recommendations of books on Newtonian cosmology (without reference to general relativity)

I only know basic special relativity, but am interested in learning Newtonian cosmology. I have heard that on introductory level, most of the material can be generated purely from Newton's work. I am ...
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122 views

Kinetics energy with different reference frame (a fighter plane shoots a bullet)?

Let say a plane flights at 1km/s, shoots a 2kg projectile at 1km/s, so to the Earth, the projectile flights at 2km/s with 2*2*2/2 = 4MJ. The same gun when fixed on Earth, shoots the same 2kg ...
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41 views

Motion of charge particle under electric and gravitational fields

I am working on one experiment in which the charged particle falls under the effect of gravity and passes through the electric field in between. I want to know what is the charge of the particle? ...
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1answer
66 views

Mass spring system, elongation of the spring [closed]

Is it possible to calculate the elongation of a spring with only the length of the spring, a spring constant and the mass that is attached to the spring?
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45 views

What's wrong with this calculation of the center of mass of a triangle?

Find the center of mass $(x_G,y_G)$ of a homogeneous triangle of mass $m$. Divide it into infinitesimal rectangles of width $dy$, length $x$, mass $dm$ and area $dA$. We have $d A = x dy $ ...
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Conserved quantities in the cart and pendulum problem

A problem on an assignment I'm doing deals with a cart of mass $m_1$ which can slide frictionlessly along the $x$-axis. Suspended from the cart by a string of length l is a mass $m_2$, which is ...
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1answer
40 views

Why in analysis of coupled oscillator, restoring force for uncoupled condition is taken in account?

If the pendulums were free & either one were displaced a small distance $x$, the restoring force would be $m{\omega_0}^2 x$. But in the present situation the coupling spring is stretched a ...
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1answer
92 views

Weight of an object at different angles [closed]

I'm trying to either find a calculator online or help with an equation to work out how much weight I'm lifting when I pick up my dirt bike off the floor [edit: when it's lying on it's side on the ...
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0answers
24 views

Will the center of mass of the whole system change when object swims on curved surface?

In the example given here, the object can move on the frictionless surface of the sphere by changing its shape periodically. So will the center of mass of the whole system change after the object ...
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2answers
128 views

Second Law for Rotational Motion

Moment of inertia is analogous to mass, and angular acceleration is analogous to linear acceleration. What is analogous quantity to net force? In other words, what is moment of inertia*angular ...
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2answers
162 views

Lagrange's equation implying Newton's 2nd law?

The typical first application of Lagrange's equation is showing that it implies Newton's law for a particle whose Lagrangian is $L=\frac{1}{2}mv^2-V(x)$. Plugging this Lagrangian into Lagrange's ...
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1answer
98 views

How to draw the free body diagram of this? [closed]

There is a smooth light peg at C. The system is in equilibrium. The ground is rough. How do I draw the free body diagram for this? Here is the system, and my attempt.
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1answer
65 views

Coriolis force in free fall: Directions?

Inspired by this Phys.SE question, Coriolis force in free fall, I have to ask: Why does the Coriolis force act in the east-direction? I would say, if I jump from a high distance and look at the ...
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1answer
69 views

Is the force experienced by a particle influenced by its distance to the focus of the force? [closed]

Is the force experienced by a particle influenced by its distance to the focus of the force?
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56 views

Hitting the center of percussion

I have a couple of questions about the CP The formula is : $$b=\frac{L^2}{12A}$$ where b is the distance from CoG, therefore if L = 1 (and M = 12), the distance from the center of gravity be ...
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2answers
87 views

Intuitive understanding of Lagrange point L3

I learned about Lagrange points today and the physics behind L1, L2, L4 and L5 make intuitive sense to me. But I'm stumped by L3. Wikipedia says "L3 in the Sun–Earth system exists on the opposite ...
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0answers
24 views

A more rigid explanation of “path of least resistance”

In order to try to understand the centripetal force and more specifically how it works for cars, I watched this YouTube video: https://www.youtube.com/watch?v=bB6R1rx5bOA The video offers a good ...
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1answer
204 views

Elastic Collisions and Relative Velocities

In a 1D elastic collision, it is well-known that the relative velocities of the two objects (before and after the collision) are reversed. What is the extension of this result to 2D or higher? Is ...
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1answer
62 views

Wheel slowing down with constant acceleration

A wheel of radius $R$ spins about its center with a centripetal acceleration of $v^2/R$. I get that the acceleration at all points on the rim of the wheel point towards the center of the wheel. But, ...
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2answers
165 views

Is momentum conserved in the collision of a ball with a hanging rod?

Suppose we have a situation like A ball of some mass $m$ with some velocity collides with rod hinged at point $A$. Is momentum conserved in this situation? I know that hinge will give impulsive ...
2
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1answer
58 views

light falling on a completely reflecting friction less mirror

If you had a perfectly reflective mirror whose face was perpendicular to the ground and was kept on a friction less track on the ground, and you shined a flashlight on it, what would happen? Would ...
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4answers
898 views

Is the work done walking up an escalator in the same speed and opposite direction of the escalator zero?

Work equals force times distance, but what about walking up an escalator in the same speed and opposite direction of the escalator? In the frame of the ground, the distance is zero so the work must ...
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1answer
179 views

How to observe Newton's third law violation? [duplicate]

I met a statement, that Lorentz force disobeys the third Newton's law. Is this true? Also I met some setups, where it was stated, that third law is violated. Also I met some explanations about WHY ...
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3answers
67 views

Work power and energy

When you push your bicycle up on an inclined the potential energy of the bicycle and yourself increases. Where does this energy come from?
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3answers
143 views

How is it that Force = Mass $\times$ Length / Time ^2?

I understand how $F=ma$ but what I am looking for is a diagram, idiom or concept that explains how force can be explained (in a partial layman's terms) as a combination of the dimensions; Length, Mass ...
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3answers
162 views

Newton's first law: unclear multiple choice question

Everyone knows that a body with no external forces acting on it remains at rest or moves with a constant velocity. But how would you answer the following multiple choice question: Question: A body ...
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1answer
40 views

Prove thrust is double the dynamic pressure across a nozzle

I'm trying to teach myself some of the content from 'Rocket Propulsion Elements' by George P. Sutton. After reading over the first couple of chapters feeling like I understood everything, I came ...
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3answers
357 views

Car “oomph”: power or torque?

Two of the most important magnitudes that characterize a car's engine are maximum power and maximum torque. How are those two magnitudes related to the sensation that the car has "oomph" or is ...
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0answers
55 views

Why is it harder to flip my cell phone about one axis than the other two? [duplicate]

There are three ways (three differenent axis about which) I can flip my cell phone - over the front (like a frontflip), about the center (like a disc of pizza dough being spun by a baker), and over ...
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0answers
28 views

Lovely flow rate [duplicate]

How can we calculate the measure of the air flow rate when it is coming out of the balloon? (I mean that which parameter affects that? For example, the measure of balloons neck or the ratios or ...
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0answers
58 views

How much energy does it take to hold a bag? [duplicate]

I'm holding a bag with some mass $m$. The force required for not letting it fall is equal to its weight $m \cdot g_L$ (where $g_L$ is the local gravity, assuming Earth this is $\approx 9.8 \; \text{m} ...
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1answer
70 views

Finding the centripetal force at any random point in a wheel which is rotating as well as translating

If we have a wheel which is decelerating due to friction with acceleration $-A$ and angular acceleration $-\alpha$, and we want to find the acceleration at any point, then we can simply find it using ...
2
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2answers
95 views

Has this double-slit experiment been performed?

A weak, single photon, source is controlled by a fast shutter and directs photons toward a double-slit. Quite far beyond the slits, compared to shutter speed, is the photon detector (perhaps a film). ...
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1answer
485 views

Kinetic energy of an expanding sphere [duplicate]

In the study of Newtonian stellar structure, Weinberg (1972) writes The uniform dilation of a sphere with uniform density will give it a kinetic energy $$U=\frac{3}{10}M\dot R^2$$ I don't ...
2
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1answer
60 views

Ball's opposite rotation caused by friction

Assume that you push a ball like in the picture (along the red line) with your hand with a some force. The ball will move forward while its rotating in this way: And after some movement, the ball ...
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1answer
39 views

Replace the force system with a single force [closed]

Please I need a quick answer I have an exam tomorrow
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2answers
71 views

Can anyone kindly help me with these sign conventions?

Since I have some confusions with the sign conventions , I have finally drawn up the following conclusions . Plz check if the following are correct .... ( I have taken all motions directed upwards as ...
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1answer
42 views

Rolling on a frictionless pond

I have a doubt about one of the questions in my textbook. Q- You are standing with your bag in your hands in the middle of a friction-less pond. How can you come out of the ice? There is of ...
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1answer
60 views

Statics question: Calculate thrust force [closed]

First and foremost can someone explain what is being asked here please?
3
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4answers
170 views

What starts the conversion between GPE and KE?

When researching GPE and KE conversion, lots of websites say that as an object with GPE (Gravitational Potential Energy) falls, that GPE is converted into KE (Kinetic Energy), so there is less GPE and ...
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2answers
321 views

3D frame stiffness matrix local to global

I am working on a simple script to be able to solve frame structure using direct stiffness method. I am having following stiffness matrix for 2 node frame element: What is the correct way of ...
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2answers
87 views

Integrate the law of universal gravitation to get position [closed]

I'm trying to write Physics simulation software which simulates gravitational and electric forces between $n$ bodies. I know how constant acceleration is integrated to get distance, but I have no ...
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2answers
98 views

How does gravitational potential energy increase, if field decreases as $h$ increases?

(In the following constants are ommitted) Let $ M = 50, m = 5, h = 5$. Then $$ \text{Potential Energy} = \frac{50\cdot5}{5} = 50.$$ While after increasing the height $h$: $ M = 50 , m =5, h =10 ...
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1answer
131 views

Conservation of energy during rolling without slipping?

Say there's a cylinder laying on a flat surface, and the surface is rested on frictionless ice. Attached to the surface is an engine that is attached via a string to the center of the cylinder, and ...
2
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0answers
80 views

Rod rotated by elastic string [closed]

A uniform rod $AB$ of length 2m and mass 1kg, has a mass of 1kg attached at $B$. It can rotate freely about a horizontal axis through $A$. The end $B$ is attached by means of a light elastic string ...
9
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3answers
226 views
+100

Is ordering players by height beneficial in a game of tug of war?

This can be considered a follow-up turn-around question for this similar question. I recently came across this interesting analysis of the game of tug of war. One of the closing discussions is the ...
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1answer
69 views

Does Newton's 3rd Law apply to friction?

Supposed body A slides on a surface. The will be a kinetic friction that acts on body A and opposite its relative motion. However, is there a kinetic friction that acts on the surface too i.e. the ...
2
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0answers
151 views

Modelling an Inelastic Collision

I've attempted to model the inelastic collision between a moving mass and a large stationary object, e.g. dropping an ball on the floor, for analysing the approximate kinematics and heat dissipation ...
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1answer
139 views

Thought Experiment: An object falling indefinitely under gravity?

So the other day, I devised this thought experiment: Consider an infinite tunnel, and you drop a coin of mass $m$ into it. Considering the effect of gravity to be applicable and neglecting air ...
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1answer
69 views

Does a projectile always meet a freely falling body when aimed at it? [closed]

When we aim a projectile at a freely falling body why does it always meet it irrespective of the range and speed.