Classical mechanics Definition and 1000 Threads

Homework Statement This is Exercise 1.19 in Goldstein's Classical Mechanics 2nd edition. Self-study, not for a class. Two mass points of mass ##m_1## and ##m_2## are connected by a string passing through a hole in a smooth table so that ##m_1## rests on the table and ##m_2## hangs suspended...

Homework Statement I was recently assigned an assignment where my instructor told us to come up with an idea for a numeric classical mechanics problem that is solved by computer methods. Some ideas the instructor gave was to simulate motion of a sun-earth-moon system or simulate the tides of a...

1. Homework Statement FInd acceleration and tension. Take g=10m/s^2 2. The attempt at a solution By drawing the free body diagrams of every block and simultaneously solving all the equations, I got the answer acceleration= 30/7 m/s^2, which is also correct. But when I try to treat all the...

Homework Statement A force field in 2-d F~ = −kr(rˆ) with U(r) = k(r^2)/2 acts on a particle of mass m. The particle is now in a non-circular orbit. In terms of the particle’s angular momentum L and energy E, d) What is its closest approach to the origin? e) What is its furthest distance from...

I'm reading Goldstein's "Classical Mechanics", first chapter, and am confused about what's going on in equations of forces and work in systems of particles. For example, Goldstein calculates work done by all the forces, external and internal, in evolving the system from state ##1## to state...

Hello, I'm sure most of you are already familiar with the book "Mechanics" by Landau and Lifshitz. There's a section that I do not understand. In section 4 towards the end they mentions that "It is easy to see that the mass of the particle cannot be negative." They then give the argument that...

Okay so I have a question about time dilation, kinetic energy and classical mechanics. My question is, if an object were traveling at very high relativistic speeds and experienced time dilation, would the time it experience and measure during the travels be equivalent to the travel time if it...

Homework Statement [/B] Consider a mass m moving in a frictionless plane that slopes at an angle \alpha with the horizontal. Write down the Lagrangian \mathcal{L} in terms of coordinates x measured horizontally across the slope, and y, measured down the slope. (Treat the system as...

Homework Statement Consider a gun of mass M (when unloaded) that fires a shell of mass m with muzzle speed v. (That is, the shell's speed relative to the gun is v.) Assuming that the gun is completely free to recoil (no external forces on gun or shell), use conservation of momentum to show that...

Hi I need to relearn classical mechanics. More specifically, I need to relearn everything in this PDF: http://www.springer.com/cda/content/document/cda_downloaddocument/9783319195957-t1.pdf?SGWID=0-0-45-1509999-p177402416 However, since I have taken this course before, I want to be a little...

So hi everyone, I'm a freshman in Physics and in a couple weeks I'm going to start my second semester, with Chemistry and two exams of Classical Mechanics (Theoretical and Practical). In our first semester we had Calculus, Linear Algebra and C Programming. Since our Calculus program went as far...

Hey guys I'm a sophomore in college currently taking physics 2(intro E&M), Multivariable calculus, and Differential Equations. I was hoping some of you guys could recommend some good books for intro mechanics and E&M. I'm currently using University Physics by Young in my E&M class, and I used...

Hi all! I'm super lost on this homework question. I tried asking the professor but was kind of brushed to the side. My vector calculus knowledge is pretty limited (I had an unfortunately experience in that class). Anybody have any ideas on how to go about solving for this? It's a problem out of...

Homework Statement A rocket with an initial mass of 60,000kg ignites its engines and burns fuel at a rate of 300 kg/s with an exhaust velocity of 2220 m/s. How long after the engines start does the rocket lift off the ground? Homework Equations From Newton's second law F = Ma this equation can...

I got a copy through interlibrary loan. 1950 and it looks great. While the textbook I bought in 2012 for $60 has the pages all warped and turning yellow. They don't make 'em like they used to. I can buy a used hardcover copy of the first edition for $21. I might go for that. Some joker...

Homework Statement A rigid “T” consists of a long rod glued perpendicular to another rod of length l that is pivoted at the origin. The T rotates around in a horizontal plane with constant frequency ω. A mass m is free to slide along the long rod and is connected to the intersection of the...

Homework Statement Consider a massless rod of length $L$ with a small mass $m1$ attached on one end, and $m2$ attached on the other end. The rod is initially in the vertical position at rest on a frictionless surface, with $m1$ on bottom and $m2$ on top. A small impulse is applied to the top...

Hi guys, I got one confusion when reading Goldstein's Classical Mechanics (page 20, third edition). After getting the equation, then it says that Note that in a system of Cartesian coordinates the partial derivative of T with respect to qj vanishes. Thus, speaking in the language of...

Hello, Per your guidance I'm running through the 2nd edition of an introduction to mechanics. I'm only in the 1st chapter and all the problems are conceptual with no sign of answers. Does anyone know where I can find a manual? Or maybe an alternate source of problems with answers?

I think I have an interesting thing to say on the foundation of classical mechanics and I wonder what would be the best journals to submit a work on that topic.

Hey, I'm one of those people who's been trying to learn Physics for ages before finishing high school (writing it down like this really makes me sound like some hopeless nerd with nothing better to do..) but never got around to doing it because my calculus knowledge sucks so much. :-) My...

How does one arrive at the following equation to approximate spring constant for solids... using Hooke's Law F ∝-x ⇒ F = -kx and strain∝stress ? k = (m/a2) × (K/ρ)½ where k≡spring constant m ≡ mass of a single atom a ≡ atomic spacing K ≡ bulk modulus ρ ≡ density

I can't convince myself that the situation in this picture is possible in reality though I know the physics works. I feel that it won't work as the workers are not glued to the platform can anyone find a demonstration to verify it .please (I'v searched youtube as much as I could) people lifting...

I'm looking for a book that has problems and explanations (not necessarily background theory) about mechanical systems. Consider the picture below for reference. The idea is I want to get a hold of energy and impulse methods for solving problems like this, eventually the book would have a...

I've asked my students about this before. I asked them what they expect to happen, and then gave them the weekend to ride a bus or a train with a balloon and see for themselves. When they came back to class, it often created quite an interesting discussion on why they were puzzled.

Homework Statement Homework Equations 3. The Attempt at a Solution [/B] Hello guys,I posted images since its easier to write equations.Please can someone help me check this, if this is correct so far, then i should be able to find the velocity at C, using kinetic energy?

Homework Statement A particle of mass m is on a massless string of length 3a, which is held horizontally across with a tension T(which you can assume doesn't change with the small vibrations). The particle is a distance of a from one of the edges. Set up a diff. equation that describes the...

What parts of Classical Mechanics must someone know before studying Quantum Mechanics in order to understand the former in all its glory? Thank you

Homework Statement [/B] A thin light string is wrapped around a solid uniform disk of mass M and radius r, mounted as shown. The loose end of the string is attached to the axle of a solid uniform disc of mass m and the same radius r which can roll without slipping down an inclined plane that...

Homework Statement This is a general query not a specific problem. In several questions in rotational dynamics they ask the trend in angular acceleration and angular velocity.In one of them they released a rod from horizontal position and asked if the angular velocity and angular acceleration...

Homework Statement [/B] A block of mass m is attached to a spring with a force constant k, as in the above diagram. Initially, the spring is compressed a distancex from the equilibrium and the block is held at rest. Another block, of mass 2m, is placed a distance x/2 from the equilibrium as...

Homework Statement [/B] What is the effective spring constant for the system of the two springs, perfect pulley, and string shown on the left for it to be modeled by just one spring (constant keff) as shown on the right? Use only the variables k1 and k2 in your answer. The Attempt at a...

Hi, I was wondering what textbooks I should be looking at to learn classical mechanics. I have spent a lot of time looking, but none of the ones I found had what I was looking for. For example, one book would cover all basic concepts in classical mechanics, but then it wouldn't cover more...

Homework Statement A block of mass M is positioned underneath an overhang that makes an angle θ > 0 with the vertical. You apply a horizontal force of Mg on the block, as shown in the figure. Assume that the friction force between the block and the overhang is large enough to keep the block at...

Why is Quantum mechanics probabilistic? what prevents it from being deterministic, like classical mechanics ?(is it the lack of information about the processes and the forces applied at this scale?)

Homework Statement Given the force ## \vec{ F }(x) = (-12x + 6) \vec{i} ## ; find kinetic energy ## T## at the point ##x=2## and trajectory of a particle ## \vec{r}(t) ##, given that ## \vec{r}(t=0)=\vec{0}## and ##\dot{\vec{r}}(t=0)=\vec{0}## . 3. The Attempt at a Solution Since...

Homework Statement A particle of mass m=4.0 kg is moving along the x-axis. The particle is being acted upon by a variable single force F⃗ , directed along the x-axis. At t=0 s, the particle is moving at v_0=−3 m/s. What is the first time t>0 when the particle comes to a stop momentarily...

Homework Statement Point transformation in a system with 2 degrees of freedom is: $$Q_1=q_1^2\\Q_2=q_q+q_2$$ a) find the most general $P_1$ and $P_2$ such that overall transformation is canonical b) Show that for some $P_1$ and $P_2$ the hamiltonain...

Homework Statement In the image uploaded below, a boxed shaped object is shown. It is floating in water so the forces that act on it are buoyancy and gravity. The first and the last compartments are filled with evenly distributed weight. The middle 2 compartments are empty. Specifics are...

Homework Statement A cylindrical container of water with a radius of 6.0 cm is placed on a phonograph turntable so that its outer edge just touches the outer edge of the turntable. The radius of the turntable is 14.5 cm, and the turntable rotates at 33 and a 1/3 revolutions per minute. How much...

This problem is an example from Mosca and Tipler, 9-13, 6th edition. I believe the books equation for the acceleration of the system is incorrect according to my work... Anyway, here goes 1. Homework Statement "Two blocks are connected by a string that passes over a disk pulley of radius R...

A small block of mass m slides on a long horizontal table when it encounters a wedge of mass 2m and height h The wedge can also slide along the table. The mass slides up the wedge all the way to the top and then slides back down, never getting over the top. All surfaces are frictionless...

Dear Physics Forum advisers, I am a collegiate junior with double majors in the mathematics and computer science. I bought a classical-mechanics book written by Herbert Goldstein in order to aid my current undergraduate research, grow my curiosity in the physics, and prepare for upcoming...

Homework Statement The statement of the question is:A chain of uniform linear mass density ##\rho##, length ##b## and mass ##M## hands as shown in the figure below. At time t=0, the ends A and B are adjacent, but end B is released. Find the tension in the chain at point A after end B has...

The reason we can choose a frame of reference arbitrarily is that a physical system is not dependent on an absolute position, orientation or time. According to Noether's Theorem, the invariance of a system under a change of position is equivalent to the momentum conservation law. In the same...

In Matrix, Morpheus shows how to jump. He jumps easily, but Neo falls in his first jump. Morpheus’ jump takes 4 s and Neo’s fall takes 7 s. Distance between the buildings as L and height as h and consider that Neo falls at the middle of the distances, L/2. If both 1 of them know a bit of...

Homework Statement Two projectiles are launched simultaneously from the same point above the flat terrain. The initial speeds of the projectiles are the same. Each projectile’s velocity makes the same angle with the horizontal. However, projectile A is launched above the horizontal and...

Homework Statement [/B] A simple pendulum is pulled sideways from the equilibrium position and then released. I figured this part out - Immediately after the pendulum is released, the net force acting on it is directed: it is perpendicular to the string (I REASONED THAT THE DIRECTION OF...

Homework Statement Two cyclists, Anant and Beth, are standing on a straight road a distance d=22.0 m apart. Simultaneously, they begin to move toward each other, Anant with acceleration a_A=0.2 m/s^2 and Beth with acceleration a_b=0.10 m/s^2. Just as they begin to move, a bee, sitting on...

Homework Statement Text from a classical mechanics textbook ( uploaded picture ) shows 2 diff equation describing the motion graphically presented in the uploaded picture. How were these set up? Homework EquationsThe Attempt at a Solution I don't have a slightest clue as how are these...