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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Does an athlete's proficiency at luge depend on his mass?

I was watching the men's luge ride with my dad. My dad said, the mass of the athlete must be at an optimum level so that he wins. I said, his volume should be minimum, but it has nothing to do with ...
0
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2answers
150 views

Is rotational motion conditioned to a central force?

We know rotational motion as a combination (a resultant) of two effects the tangential velocity and a centripetal force. Does rotational motion turn into linear motion at the same instance this ...
4
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3answers
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Why does the tension on the pulley in an Atwood machine not equal $(m_1 + m_2)g$?

Consider the following simple Atwood machine with an ideal pulley and an ideal string According to my textbook, the tension on the clamp that holds the machine to the wall equals $2T$. I don't ...
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1answer
224 views

Synchronizing Pendulums

Assume we have a frictionless pendulum of length $l$ with mass $m$. This pendulum hangs from some weightless contraption, which is itself bolted to a platform. This platform can move horizontally in ...
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1answer
72 views

Regarding the centrifugal force in a 3-body system

In our lecture about general mechanics, we have treated the simplified 3-body system consisting of the Sun, the Earth and the Moon. We assumed that the moon does not have any influence on the Sun or ...
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0answers
37 views

What is $p$ in this candidate solution for the motion of N masses?

In this problem: Consider the system of $N$ masses shown in the figure (see picture 1). a) Using the approximation for small angles, write the equation of transverse movement for the n-th ...
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1answer
75 views

Uniform Circular Motion: v = v_0 + (a_T)*t as a vector VS as a scalar equation

First, I'll explain my confusion, which may be enough for someone to clarify my misunderstanding. Second, to give context, I will give the homework problem (which I've solved successfully) which ...
0
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1answer
31 views

Why does angle deviation of a satellite not captured my Mars decreases as the Velocity of the satellite increases?

When a satellite is not captured by a planet, it is moving sufficiently fast. so why is it that the angle deviation of the satellite decreases as its initial velocity increases?
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0answers
61 views

Modeling with First Order Equations [closed]

A ball with mass 015kg is thrown upward with initial velocity 20m/s from the roof of a building 30m high. There is air resistance of magnitude v^2/1325 directed opposite to the velocity , where the ...
3
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2answers
223 views

Is there a better approximation of drag (other than quadratic drag)?

This is a student inquiry sparked by sheer curiosity. Wikipedia states the drag equation, $F = 1/2v^2pC_dA_c$. (p = mass density of fluid/gas, v = velocity, c_d = drag coefficient, a_c = cross ...
4
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2answers
278 views

If $F=ma$, how do can we experience both gravity and a normal force even though we are not accelerating

So as I sit in my chair, I experience a gravitational force pushing me into the chair and I'm also experiencing the normal force of the chair pushing back at me so I don't fall. According to Newton's ...
0
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1answer
128 views

Uniform Circular Motion Confusion

Having some problems when calculating this problem: A fly lands on an old record player, while a 7'' O.D. 45 RPM record is playing. If the fly lands on the edge of the record, determine the records ...
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3answers
535 views

Force when acceleration is zero

i tried to find it in books but i was unable to do so and i am not able to understand this and I couldn't think of a better example. i repeat. its just an example. if i punch someone's face with my ...
5
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9answers
841 views

Did relativity make Newtonian mechanics obsolete?

Did Einstein completely prove Newton wrong? If so, why we apply Newtonian mechanics even today? Because Newton said that time is absolute and Einstein suggested it relative? So, if fundamentals are ...
0
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0answers
332 views

Inclined plane problem

FOR THE GIVEN PROBLEM AND SOLUTION BELOW 1) The problem statement, all variables and given/known data: A student pulls on a box up an incline of 10 degrees. The student pulls with a force of 180 ...
0
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0answers
106 views

Tension in a chain fountain

I was reading the following paper: http://arxiv.org/abs/1310.4056 There were a few things I couldn't follow: 1) Equation (0.1) $T_C/r=\lambda v^2/r$ I understand this takes the form of ...
0
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1answer
128 views

Block on cart, equation of motion

Consider a rigid block of $b \times h$ having mass $m$ on cart (as depicted below). The cart is given an acceleration $a$, this leads to overturning of the block. The angle of rotation is indicated by ...
1
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1answer
2k views

Calculate work done in an inclined plane [closed]

How can you calculate the work done by a force (of unknown quantity) exerted on a 10kg block on an inclined plane. The force is pointing upwards and parallel to the incline (which is inclined 30 ...
0
votes
1answer
67 views

Earth's graviational pull at the centre [duplicate]

Suppose, I somehow happen to dig a hole diametrically through the Earth (neglecting all constraints like molten core etc ) ... and I throw an object from one side of the hole, will it reach the other ...
0
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0answers
88 views

Spring Force in a Dynamic Equation

I am working on dynamic simulation of a bipedal robot, I have dynamic equations of a preliminary structure. But Now I have to add some springs to the dynamics. I am having a problem of how to account ...
0
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3answers
175 views

Quantum explanation of Newton's Third Law of Motion

Newton's law states that for every action there is equal and opposite reaction. This law explains how rockets fly in space and accounts for the the majority of the lift action generated by a ...
1
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1answer
142 views

Rope on an inclined plane problem

My book says the answer is (a)zero but i don't understand how it came zero. What will the acceleration if horizontal level of the two ends of the rope are different?
0
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0answers
15 views

Reference request for motion & related topics [duplicate]

I'm starting a Robotics course at grad school and I could use some help to relearn and revise my concepts in the following topics : Kinematics Rigid Body Dynamics Rotational Motion and Linear ...
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3answers
439 views

Physical plausibility of the Inverted Pyramid puzzle [closed]

The inverted pyramid puzzle has the following premises: A giant inverted steel pyramid is perfectly balanced on its point. Any movement of the pyramid will cause it to topple over. Underneath ...
1
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2answers
108 views

Acceleration at two points on a rigid body

The rod AB is falling while sliding on the friction-less wall and the floor. I need to find the acceleration of the points A and B. I am sure that the point A is freely falling, so its acceleration ...
1
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1answer
106 views

Angular Velocity after a frictional impulse

I am modelling 2D physics collision into simulations. In Physics for Game Programmers, Grant Palmer book, the velocity Vn1 after collision is mentioned to be independent of the friction coeff. ...
0
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4answers
357 views

Does car lose kinetic energy when turning?

I am writing simple car simulation. Assume non friction, then in straight line the car doesn't lose speed. But what if the car is turning, there should be some kinetic energy loses to change the ...
0
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1answer
64 views

Some subtleties in direction of drag force

Consider a body released from a height $h$ and assume a drag force is linearly proportional to the velocity. Then by Newton's Second Law, $$m\mathbf{\dot{v}} = \mathbf{F_g} + \mathbf{F_{drag}} = ...
0
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3answers
96 views

How was this formula in my textbook was derived?

How is this formula derived (it is present in one of the hundred pages of my textbook about physics and fundamental physics) In the case of a system of particles $P_i$, $i = 1, …, n$, each with mass ...
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2answers
363 views

Does Newton's third law of motion fail anywhere?

Does Newton's third law of motion fail anywhere, including particle physics and other advanced topics?
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2answers
203 views

2 bodies separated by a rope [closed]

Say you have two bodies connected by a "weightless" rope, one hanging from a ledge on a pulley (classic pulley problem). If the body that is on the surface and being pulled by the object hanging ...
0
votes
2answers
149 views

Find the elongation in the wire [closed]

Two wires of diameter 0.25 cm, one made of steel and the other made of brass are loaded as shown in fig. The unloaded length of steel wire is 1.5 m and that of brass wire is 1.0 m. Compute the ...
1
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3answers
97 views

Can we feel our own weight (can we feel normal reaction)?

If we place something on our head, we can feel it's weight pushing us down. But we ourselves apply normal reaction which balances the weight of the object and stops it from actually pushing us down. ...
8
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2answers
960 views

Non-Constant Acceleration due to Gravity

Recently, I had the first physics lab for my university physics course. This lab was fairly simple, as we were merely using a computer and a distance sensor to graph the position, velocity, and ...
0
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2answers
350 views

Energy transfer in elastic collision [duplicate]

In a given reference frame where object 1 (with known mass and velocity) collides elastically with object 2 (with known mass and velocity), can we identify which object loses kinetic energy? Is it ...
2
votes
1answer
91 views

What is the constant $K_1$ in these orbital equations?

I want to compute the derivatives of argument of periapsis and longitude of the ascending node of the orbit of a GPS satellite from the following formula. $$\frac{d\Omega}{dt} = -K \cos{i} \\ ...
5
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2answers
3k views

Perfectly centered break of a perfectly aligned pool ball rack

Imagine the beginning of a game of pool, you have 16 balls, 15 of them in a triangle <| and 1 of them being the cue ball off to the left of that triangle. Imagine that the rack (the 15 balls in a ...
9
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4answers
624 views

Is the second law of thermodynamics a fundamental law, or does it emerge from other laws?

My question is basically this. Is the second law of thermodynamics a fundamental, basic law of physics, or does it emerge from more fundamental laws? Let's say I was to write a massive computer ...
-5
votes
1answer
341 views

Proof for torque=force*perpendicular distance to line of action of force [closed]

I want to derive from first principles the proof for magnitude of torque about a point O = perpendicular distance from O to the line of action of the force * magnitude of the force. I want to derive ...
0
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3answers
2k views

What is difference between Acceleration due to gravity and Gravitational field intensity near the Earth Surface?

I have read in so many standard books that Gravitational field intensity near the earth surface and acceleration due to gravity near the earth surface are Two Different physical quantities with same ...
1
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1answer
231 views

Pseudo Force Other Than Centrifugal Force In A Rotating Frame

I read in HC Verma that if we are observing the motion of a body from a rotating frame and the body under the observation is NOT in motion with respect to our frame than centrifugal force is the ...
3
votes
4answers
500 views

What is difference between Inertial mass and gravitational mass [duplicate]

I recently read that the mass we deal with in Equation $F=Ma$ is called inertial mass and the mass we deal with in $F=Mg$ is gravitational mass. Suppose I am taking a same ball in a free fall and in ...
0
votes
1answer
332 views

Simple Harmonic Motion Question - Block on Platform [closed]

A platform is executing SHM in a vertical direction with an amplitude of $5$ cm and a frequency of $\frac{10}{\pi}$ vibrations per second. A block is placed on the platform at the lowest point of its ...
7
votes
2answers
227 views

Tension in string due to surface tension

Suppose you take a loop of string and place it on the surface of a liquid, the string should become taut due to surface tension. How would you be able to calculate the tension in the loop of string? ...
27
votes
10answers
14k views

Why is acceleration expressed as m/s/s?

I'm a philosophy student (I, regrettably, don't know calculus or much physics). Last year I spent some time learning how work, power, speed, velocity, energy, force, and acceleration relate. But I was ...
2
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0answers
79 views

Travel time in elliptical orbit around the sun

Hi I'm calculating a problem, and I think it ought to be correct - but the result I get isn't. The problem is described as follow: A spacecraft is traveling from Earth to Venus in an elliptical, ...
0
votes
2answers
52 views

A Kinematics Problem [closed]

Problem: From the top of a building of height h = 100 m I throw a stone up with velocity 10 m/s. What is the maximum height it reaches, and when does this occur? First I solved for $h_{max}$, ...
4
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2answers
266 views

Does Galileo's Tower of Pisa argument contradict quantum mechanics?

(My questions are at the end, but they may not mean much without explanation below.) Galileo argued that because the mass of a falling object can always be redistributed in ways that asymptotically ...
0
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2answers
44 views

Why turning velocity of star towards point “A” makes it's satelites, change their apoapsis to side opposite of velocity vector?

Why turning velocity of star towards point "A" makes it's satelites, change their apoapsis to side opposite of velocity vector? Sentence above turned a bit crazy or not understandable (possible ...
-3
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1answer
74 views

Forces: why are the theta's equal?

I found this figure in my physics book, the task says that the incline got a angle of theta. How do figure out that the gravity and the y-axis got the same angle as the incline? There is no ...