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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Which of the Physics textbooks would you recommend I read this quarter (Analytical Mechanics)? [duplicate]

My Analytical Mechanics class this quarter has one required textbook: "Classical Dynamics of Particles and Systems" by Thornton & Marion and three recommended readings: "Mechanics" by Landau ...
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0answers
23 views

Simple question relating to physics prac reports

I am writing a physics practical report relating to the elasticity of materials relating to their momentum in a collision. I have values for the elasticities that are all within 2% of each other but I ...
2
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1answer
35 views

What are the tidal effects of Io on Jupiter?

I recall reading an essay by Asimov (I think) around 1980 stating that the tides are a function of a power of the diameter of the primary, so (surprisingly) small close moons of Jupiter raise large ...
2
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1answer
26 views

Is a rope wave a perfectly transverse wave?

When i create a disturbance in a rope.What is happening at the particle level.I imagine the particles and the forces on the particles like this: According to my model there should be some ...
0
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1answer
29 views

Solving Lagrangian equations of motion for two point-bodies with gravitational interaction

I would like to solve the equations of motion with the Lagrangian function for two point-bodies that interact gravitationally via the potential $$V= {-Gm_1m_2 \over r_{12}} $$ where $$r_{12} = **r_1 ...
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1answer
26 views

What causes angular and linear deceleration in a sliding and rotating ring?

I was solving an AP Physics problem involving a ring sliding and rotating over a frictional surface. When I started to think about why the ring eventually comes to a stop I started to become confused. ...
2
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1answer
59 views

Can someone explain this solution for the motion of a falling chain?

In an example of Marion's classical dynamics 5th edition, I found example 9.2 not making sense, which states: My questions are: The horizontal motion cannot be ignored even in the idealized ...
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0answers
49 views

Understanding Millikan's oil-drop experiment

This is quoted from A.P. French's Newtonian Mechanicsabout Millikan's oil-drop experiment: The droplets randomly produced in a mist of oil vapor are of various sizes. The ones that Millikan found ...
2
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3answers
60 views

Why isn't the terminal velocity completely achieved but only asymptotically achieved due to action of resistive force?

Motion against resistive forces is given by: $$F_0 - R(v) = m\frac{dv}{dt}$$ where $R(v) = A.v + B.v^2$. Terminal velocity can be found by solving $$B.v^2 + A.v - F_0 = 0$$ ie. $v_t$ is the velocity ...
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1answer
32 views

How would a plane hitting a ball move (opposite of Pong)?

When a moving ball hits a stationary plane at an angle of incidence to the normal, it bounces away at the same angle (the angle of reflection), which is commonly understood. My question is 1) What ...
-1
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0answers
31 views

Kepler law - 2 proof (area vectors) [on hold]

How to prove Keplers second law? I tried but I could not get how to make the proof in area vectors and time Differentiated equation can't be used for area vectors then how to prove it?
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0answers
26 views

Finding the motion of an object on a spring given its mass and displacement [on hold]

A mass of $500gm$ is suspended from the ceiling by a frictionless spring, it stretches the spring $50cm$ before getting to its equilibrium position, where the mass pulling down is balanced exactly by ...
1
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1answer
24 views

How to calculate the normal force exerted by a fulcrum off-center?

So I know that $F_N$ exerted by a fulcrum right under the centre of mass for, say, a long horizontal rod, is equal to $mg$. But what if the fulcrum is off the centre of mass either to the right or the ...
1
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2answers
36 views

Period of a simple pendulum accounting for friction

The period of a simple pendulum is $$T=2\pi\sqrt{\ell/g},$$ but no where in there do I see that it accounts for friction. Does it somehow account for friction, and if not, how could you do that?
2
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1answer
26 views

Calculating wind force and drag force on a falling object

I'm trying to numerically integrate the motion of an object (say, a falling vertical cylinder). Here, there's a drag force: the wind "acting" on the body (presumably adding horizontal velocity) and ...
0
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0answers
24 views

Mass of lead balls (Cavendish experiment) [on hold]

I have to find the mass of those two lead balls, what is given is the following things: Radius ball 1 [meters] $$0.05$$ Radius ball 2 [meters] $$0.3$$ And the next formulas: where G is the ...
1
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1answer
35 views

if you have an object on an inclined slope, by applying a horizontal force would you be able to lift the object from the slope?

I am programming a free body force diagram and as part of it a am allowing the user to adjust the angle of the plane and apply a force to an object on such plane at any angle to the horizontal. My ...
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5answers
69 views

Which one acts first: friction or tension?

I have a block kept on a rough surface with a string attaching it to the wall. I pull the block opposite to the string with a certain force $F \leq \mu mg$ where $\mu$ is the coefficient of friction ...
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2answers
55 views

Why do particles of equal mass (with one at rest) undergoing elastic collisions scatter at only right angles?

This is from the Section 9.6, page 351 of "Classical Dynamics of Particles and Systems" by Thornton and Marion. By setting a up a system where mass 1 has initial momentum $m_1 u_1$ and mass 2 is at ...
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1answer
40 views

Lead bullet vs a Rubber bullet?

Our teacher says that rubber bullet is more effective than a lead bullet for knocking down a bear/human/whatever. He says that change in momentum for rubber bullet is greater than that for lead ...
-3
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0answers
52 views

Jee mains 2015 online [on hold]

A particle is moving in circle of radius r under the action of force F=ar^2, which is directed towards centre of the circle. total mechanical energy (kinetic + potential) energy of the particle (take ...
20
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9answers
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Does it take more energy to open a door when applying force close to the hinge?

Assuming an ordinary hinged door (without any springs), would it take more energy to open it when applying force in the middle of the door (point b), rather than at the end of the door (point a), ...
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1answer
42 views

Why doesn't the string slack in the motion in a vertical circle even if tension is zero?

Suppose a particle of mass $m$ is attached to an inextensible string of length $R$ and is undergoing vertical - circular motion. The centripetal force is given by the tension & its weight: $$T ...
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0answers
45 views

Newton's Second Law And Horse Racing

I'm a big racing fan and decided that I'd like to develop a better understanding of how weight impacts a horses performance. I did some searching on the internet and came across this article: The ...
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0answers
21 views

Statics: Cable with distributed loads. What am I doing wrong?

This is the problem: It says: If the maximum value for the ABCD cable's tension is 15 kN, determine: a) $h_b$ b) $h_c$ My development was: 1) Whole body (ABCD). Sum of momentums in D equals ...
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0answers
26 views

Finding speed of the speed of the ball at the bottom of a circle [on hold]

A ball of mass 4.0kg at one end of a string of length 2.5m rotates in a vertical circle just fast enough to prevent the string from going slack at the top of the circle. What is the speed of the ball ...
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0answers
14 views

Head on collision of a neutron and a atom at rest [on hold]

Let the neutron move with velocity $u$ and the mass of atom be $A$ and the initial energy be $E$. Find the energy retained in the neutron after collision. First, I applied momentum conservation, $u$ ...
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0answers
59 views

Constrained Motion involving concepts of Center of mass and Newton's Law [on hold]

For the situation shown in figure: $\hskip.75in$ I wish to calculate the speed of block at bottom-most point($\chi$), that is easily done using: $$2mgl=\frac12(2m)v_{b,\chi}^2+\frac12mv_r^2$$ where ...
2
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0answers
31 views

Tensions in a rope [duplicate]

If two tensions are acting on a rope such that they are equal (each is 10 N) and opposite (180 degrees) then what will be the total tension in the rope? I cant seem to figure out if these two will ...
-1
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0answers
23 views

Forces in equilibrium [on hold]

A homogenous beam OA with the length 4a and the mass m can rotate i the vertical plane around a horisontal axis through O and is kept in equilibrium by a wire attached in the points A and C going ...
1
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2answers
39 views

Does air density influence a football player's ability to “bend” the ball?

Whilst reading an article on nasa.gov, there was a claim that I found interesting: At higher altitudes, the density r is lower producing a larger radius of curvature and a straighter path. The ...
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6answers
9k views

Can we theoretically balance a perfectly symmetrical pencil on its one-atom tip?

I was asked by an undergrad student about this question. I think if we were to take away air molecules around the pencil and cool it to absolute zero, that pencil would theoretically balance. Am I ...
-1
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0answers
28 views

George Brown Engineering dynamics [on hold]

A 0.5 kg soccer ball at point A, is rolling at a constant velocity and rolls to a player at point B. the player kicks the ball which causes the ball to change direction and speed, it then moves in ...
-1
votes
1answer
41 views

Determine center of mass! [on hold]

See the very funny figure. I have determined the mass of center in the x-coordinate to $r/4$ but I don't know how to get the y-coordinate. The key says it's $- r/ \pi$ but I can't see how to get ...
0
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1answer
44 views

Simple pendulum cartesian coordinates

I'm reading Vibrations and Waves from French. I don't understand the following approximation when considering the simple pendulum: Referring to the last figure if the angle $\theta$ is small we ...
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0answers
26 views

Translational Velocity and Frequency question [on hold]

Ann, Sam and you take a trip to the orbiting International Space Station, bringing along a hula hoop (http://en.wikipedia.org/wiki/Hula_hoop) that is 1.02 m in diameter (= 2R) and has a mass Mh = 2.0 ...
-3
votes
1answer
38 views

Find for how much time, the car with stop and how many meters has it done [on hold]

A car with mass 1000kg moves with velocity 50 km/hour. The system of deceleration in a car is based on the principle of "force match" that is applied on each of four wheels with a force of 210 N and ...
-1
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0answers
45 views

The position vector of particle in horizontal wire [on hold]

A particle of mass $14~\text{kg}$, slides along a straight wire in a horizontal plane. The coefficient of dynamic friction $\mu_k = 0.6$ The equation of the line of the wire is $y = \sqrt{3}x$ so ...
0
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1answer
25 views

The applied and friction forces of a particle along a straight wire in horizontal plane

A particle of mass $14~\text{kg}$, slides along a straight wire in a horizontal plane. The coefficient of dynamic friction $\mu_k = 0.6$ The equation of the line of the wire is $y = \sqrt{3}x$ so ...
-2
votes
0answers
40 views

Crank slider Question [closed]

Hello StackExchange Gurus, I finally learnt how to write MathJax and please help me now. This is a crank slider mechanism. Can someone show me the relationship between angular velocities (thetadot ...
0
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1answer
34 views

If the cord has a breaking strength of 25.0 N, explain why the cord broke when supporting a load so much lesser than its breaking strength [on hold]

A picture of weight 5.0 N is suspended from a hook on the wall by a cord. The tension of the cord is 7.07 N. It was found that the picture is hung too low on the wall and was adjusted by shortening ...
-2
votes
1answer
32 views

Mechanics Question Help? [closed]

I have this question that has been puzzling me for a while, I can find the net force acting or at least express it at $6.5974-{F\over m}=a$ but can't find any way to calculate or use this to find a? ...
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5answers
86 views

How to interpret that forces do not depend on acceleration?

I was told forces can depend on time, location and velocity, but never on acceleration. At first I thought this must be wrong, thinking of $F=m\cdot a$. But I think/hope I now got what was meant, what ...
2
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2answers
83 views

Clarify excerpt from Feynman Lectures on rotations in three dimensions

In The Feynman Lectures, vol. I, chapter 20 Feynman discusses rotations in three dimensions and explains angular velocities may be added as vectors; in particular he says: What about angular ...
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1answer
46 views

Using Conservation of momentum and Energy to solve a problem [closed]

A 9kg bullet is fired horizontally into a 10 kg block of wood suspended by a rope from the ceiling. The block swings in an arc, rising 6mm above its lowest position. Find the velocity of the bullet. ...
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0answers
36 views

How do I find the momentum of a car after a turn of 90°? [closed]

I cannot solve this problem: A car ($m=4,000 \text{ kg}$) that is going north without changing its velocity at the speed of $24 \text{ m/s}$ makes a turn to the right at 90 degrees. What's ...
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0answers
31 views

How to find the velocity ratio of a pulley system? [closed]

How would you draw a labelled diagram of a pulley system with a velocity ratio of 5? How would you relate a pulley system to its velocity ratio? How would that diagram even look All I know is that ...
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0answers
30 views

Rotating rod assembly, finding the force reactions at the bearings [closed]

I need help with this problem. The solution given in my text book is very bare bones and I don't understand it. I'm have trouble with finding the moment of inertia and products of inertia. Any ...
0
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2answers
47 views

Speed needed to make a car jump from a ramp

(I've posted this question on GameDev and I've been told to ask here so I'm pasting the question) I need to make a car jump from a ramp to another, and I need this to be done using AI so I thought it ...
0
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2answers
56 views

Is potential energy an energy exists or potentiality of energy? [closed]

I want to ask whether Potential Energy is truly existing Energy - though i know the energy concept is abstract and we do not know what is energy truly as Feynman said - or it is the potentiality that ...