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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Simple Conservation of Energy Question

Deduce that the speed $V$ with which the bullet strikes the plasticine is about $160 \ m/s$ Using the conservation of energy, I equated the kinetic energy of the bullet to the potential energy of ...
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37 views

Animating Differential Equations

I was tasked with creating a $3D$ animation in Mathematica, which aims to describe the movement of a football through space as it's kicked. There are several differential equations regarding this ...
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2answers
61 views

Find the speed of a mass $m$ as it slides down a slope at an angle $θ$ starting from a vertical height $h$ using energy conservation [closed]

Note: The object starts from rest. I'm confused as to what formula for energy I should be using to solve this problem. Any ideas?
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494 views

Escape velocity at an angle

Comparing the work required for a mass to escape the Earth's gravity to the necessary initial kinetic energy gives us the escape velocity from the surface of the Earth of around $11\;\mathrm{km\cdot s^...
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30 views

Predict position of a body in an elliptical orbit in Cartesian coordinates [closed]

A spaceship is orbiting a star on a 2-dimensional plane. I know: The orbit is elliptical The mass of the star Where the star is in x,y coordinates Where the spaceship is in x,y coordinates. The semi-...
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2answers
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Parallelogram Law of Force Addition

In most of the mechanics textbooks , the Parallelogram Law of Force Addition is stated without any justification or an experiment to confirm this law. Also after introducing this law forces are also ...
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26 views

Circular Motion of body in vertical circle [closed]

A body moving in vertical circle of radius r such that the string is just tight at the highest point. The speed of particle when the string become horizontal is
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2answers
142 views

Weight Distribution of granular piles

I was recently at a farm watching piles of grain being formed in the shape of enormous cones. Each of these grain stacks weighs in excess of 50 tonnes. I am not a physicist but I am very curious as to ...
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0answers
19 views

Force exerted on a rod resting on a frictionless surface [closed]

In a very short amount of time, a force is exerted on one end of a rod(mass M and length L) that rests on a frictionless plane. The force causes the momentum to change by J. What is the velocity of ...
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4answers
73 views

Friction-Newtonian Mechanics

Here we are having two blocks of mass $2~\rm kg$ and $4~\rm kg$ on an inclined angle with angle of inclination being $30~\circ.$ The block of mass 2 kg has a coefficient of friction $\mu_1=0.2$ and ...
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30 views

How to apply conservation of energy to active noise-cancelling headphones?

Active noise-cancelling headphones add the opposite waveforms of the ambient sound in order to cancel out this ambient sound by destructive interference. I do not understand why adding more power in ...
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47 views

Trouble following an argument about a rocket problem

This is from pages 32-33 of Physics for Mathematicians. A rocket + fuel system of mass $m(t)$ is moving along at velocity $v(t)$, with its fuel being ejected at the velocity (relative to the rocket) $...
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2answers
49 views

Homework: Angular Acceleration from Net Torque [closed]

I have the correct answer but don't know how that is the correct one. My answers were way off which indicates I am missing something big but don't know what. Now the 4 torques are: t1=6.175, t2=....
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1answer
41 views

Collisions; Linear Momentum [on hold]

Let's say we got a rough surface with friction and there are 2 blocks, the block of the left has initial velocity and will collide with the block of the right, which is in rest. Consider an elastic ...
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1answer
37 views

Ratio between accelerations [closed]

I have worked on this problem on mechanics, but when I look at the answer to the problem I can't figure out why the acceleration of the block is twice the acceleration of the cylinder when the ...
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2answers
21 views

Cinematics; Equation of movement

What's the difference using the fórmulas v=d/t , or a=v/t, instead of equations of motion? I dont get it.
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1answer
117 views

Why are trains so hard to stop?

Since there are brakes on every car, shouldn't the stopping time of the entire train be the same as the stopping time of a single car? Is this because the cars themselves take a long time to stop, or ...
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1answer
27 views

Outbalancing vibrations

Consider a ship vibrating in the fundamental/principal/first symmetric mode shape (similar to that of a Bernoulli-Euler beam), induced by the main engine (similar to that of a vibration shaker). I ...
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2answers
49 views

System rigidity

What is the meaning of system rigidity in mechanics? I can't understand how to classify the system as rigid or not, and what is the effect of rigidity on the whole system. If you know anything about ...
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2answers
107 views

Physics of a sprint start

I am looking for an explanation to this illustration of a sprinter coming out of the blocks: Apparently, the production of horizontal force produces a great deal of body rotation (R1) which would ...
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1answer
108 views

Experimental data for asymmetric Newton cradle

Using a "successive impact model" (as if each ball were seperated from the other ones), I produced the following animations: You can see any combination of balls with masses of 1 or 2 (left) or 1 ...
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1answer
101 views

Can a particle pass through a point where wave function is zero?

Let's consider an infinite square well. In the first exited state there is a node at the middle of the well (i.e. wave function and thus probability of finding the particle is zero there). If I ...
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2answers
29 views

Work and energy example [duplicate]

The normal definition of Work, as far as I have read, is: Energy is transferred through work. But I just heard an educationist state this example, where there is a weightlifter who keeps up a huge ...
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A trio of spinning marbles

My little brother showed me this devised act in which he stuck three marbles in a triangular pattern When he spun any of those marbles, the triplet would first rotate normally, but moments later, ...
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1answer
67 views

Three connected balls

I'm stuck solving this problem with three small balls of masses $m$, $2 m$ and $3 m$ on a smooth table, connected by two equal, light inextensible strings as shown, and initially at the vertices of an ...
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29 views

Why does the inverse square law cause elliptical orbits? [duplicate]

I've seen it printed multiple places, here for example, that the reason orbits are elliptical is because the gravitational law has an inverse square of the radius. Why does this make the orbits ...
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34 views

Mathematical proof for elliptical orbit of planets [duplicate]

Elliptical orbits are stable for planets. But how to mathematically derive this result that a planet travels in an elliptical path? How are circular orbits less stable than elliptical orbits for ...
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37 views

Simplifying three mass, two springs system

I have a system of three equal masses connected by two equal string system. x_1 x_2 x_3 *--------*---------* ------> x M k M k M ...
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1answer
49 views

Conservative force for impulse analogous to conservative force for work done?

As force $F(x)$ can be conservative regarding work done between two points in space, can force $F(t)$ be conservative regarding impulse between two points in time?
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39 views

V-Belt: Torque on pulley and Max Tension

A V-belt consists of a driven pulley of diameter 250mm and a driver pulley of diam. 100mm , at a centre to centre distance of 170mm. the driver pulley rotates at 1440rpm, transmitting 30KW through ...
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4answers
277 views

How to solve this problem without using energy conservation

I believe most of you probably solved the following problem using energy conservation as shown here. It states a block of mass $m$ sliding on a sphere of radius $R$. I've be trying to solve this ...
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3answers
58 views

Why does overcoming inertia depend upon time?

When a paper over a glass is pulled suddenly, the coin over it falls to the water. But on pulling it slowly, the coin gets pulled along with the paper. Why does the coin in the former case not feel ...
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1answer
64 views

How to prepare mental skills to understand relativity theory? [closed]

Upto the high- school, I had to admit and write-on-exam the strange, counter-intuitive statements of relativity theory; those I could not believe. Now, I'm not a physics or math-student, (and indeed ...
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1answer
44 views

Notations used to express direction [closed]

We express direction relative to a reference point and call a certain direction positive and it's direct opposite direction negative, by convention. But, what notation should we use to express a ...
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1answer
35 views

Work done relation to potential energy

I know work done is negative of change in potential energy, I.e., $W=-(∆U)$. It means that Work done against a force (or work done on a system) increases its potential energy. And Work done by a ...
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2answers
82 views

If I throw or kick a ball, how much will the Earth move in the opposite direction?

I understand that for momentum to be conserved, if I throw a tennis ball (or kick a football) the Earth must move in the opposite direction to the ball. Obviously this is an infinitesimally small ...
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1answer
119 views

Is conservation of momentum and energy valid for non-inertial frames?

Conservation laws of momentum and energy are said to be the most basic principles of physics. Are they also valid for non-inertial frames, and in what way?
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1answer
30 views

Where does gravity get it's energy to cause tides? [duplicate]

The moon's orbital radius is fixed as a function of its velocity (I know it is actually drifting..). Since there is nothing in space to resist this velocity, it will continue orbiting "forever". Now ...
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0answers
28 views

Generalise Noether's theorem [closed]

I'm not sure how to generalise Noether's theorem. For this L, I think $B\cdot\dot{x}$ is conserved so I tried to relate F and K to this and try to show that that was conserved but got no where. any ...
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2answers
111 views

Equation for a falling body including terminal velocity

I'm making an app that times how long it takes a pebble to fall, then calculates the distance it fell. I noticed that the simple $f(t) = \frac{1}{2}gt^2$ was becoming increasingly inaccurate as the ...