Mechancis Definition and 131 Threads

Homework Statement A mass ##m## whirls around on a string which passes through a ring. Given that gravity is not present and initially the mass is at a distance ##r_0## from the center and is revolving at angular velocity ##\omega_0##. The string is pulled with constant velocity ##V## starting...

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Homework Statement A heavy mass m is attached to thin wire and whirled in a vertical circle. Then the wire is most likely to break A only when mass is at the lowest B somewhere between lowest point and horizontal point C only when mass is horizontal D only when mass is at highest point...

Homework Statement A uniform ring of mass m and radius r is projected horizontally with velocity v on a rough horizontal floor,so that it starts off with a pure sliding motion and it acquires a pure rolling motion after moving a distance d.If the coeffcient of friction between ground and ring...

Homework Statement Given a plank is moved with uniform velocity v. To which a mass is connected by a spring of force constant k. What is work done by the external agent on the maximum compression of the spring Homework Equations Work done by spring=0.5*k*x2 Work-energy theorem: total work...

Homework Statement Homework Equations The right hand section (A) has an incident and reflected wave $$y_1=Ae^{i(kx+\omega t)} +A'e^{i(-kx+\omega t)} $$ The middle section (B) has a transmission reflected wave $$y_2=Be^{i(k_2x+\omega t)} +B'e^{i(-k_2x+\omega t)}$$ Section (C) just has the...

Homework Statement Consider a charge ##q##, with mass ##m##, moving in the ##x-y## plane under the influence of a uniform magnetic field ##\vec{B}=B\hat{z}##. Show that the Hamiltonian $$ H = \frac{(\vec{p}-q\vec{A})^2}{2m}$$ with $$\vec{A} = \frac{1}{2}(\vec{B}\times\vec{r})$$ reduces to $$...

Homework Statement Find the total tension acting on a rod rotating about its end with an angular velocity of w as a function of its length x(length) Homework Equations F = ma[/B] The Attempt at a Solution Let the function be T(x) where x is the length of the rod. Considering an interval...

1. Homework Statement a circular homogenic pulley (disk) with radius R and mass of M hanging on a axis that passes through his center, the pulley rotating without friction. we wrap the pulley with a rope with a total mass of mr and length of L and in the other side of the rope we ataching...

When solving for the hydrostatic force on a surface we use the height to the centroid(hc), then when using the point of application we use the y coordinate of the centroid(yc), however shouldn't they be the same since they both start from the top surface and reach down to the object surface on...

I am a high school student looking for some amazing lectures online to study classical mechanics for a regional qualifying camp for ipho.

Homework Statement A ball is dropped vertically from a height H on to a plane surface and permitted to bounce repeatedly along a vertical line. After every bounce, its kinetic energy becomes a quarter of its kinetic energy before the bounce. The ball will come to rest after time? Homework...

Homework Statement A car moves from X to Y along a semicircular path. The radius of the path is 250 m and the time taken to complete the trip is 50 s. What is the magnitude of the average velocity and the magnitude of the average speed? can you please explain? <3 Homework Equations v = wr = 2π...

Homework Statement So here is the Problem: A big truck (m=50t) is going at 100km/h. Now the truck can't brake anymore and Superman comes to aid. He (has a mass of m=100kg) tries to stop the truck while he is wearing shoes with a rubber-texture and a friction coefficient of µ = 0.8. Assume that...

Homework Statement I need to find the period of small vertical oscillations about equilibrium position of a string whose motion can be described by the following equation: d2x/dt2 = (-g/h)*x Answer: 2π√(h/g) Homework Equations I know that the time period is given by the formula T = 2πω where...

Homework Statement So we have 65N @ 30*, 30N @ 180* and 20N at 250* Homework Equations Ncos(angle)i + Nsin(angle)jThe Attempt at a Solution Using this video I did the following. F1(65N) = 65cos(30)i+65sin30i Then using the radian circle I saw that 30* has x,y coordinates of sqrt3/2...

Homework Statement A particle of mass m moves along the x–axis under the influence of force ##F_x=-ax+bx^3## , where a and b are known positive constants. (a) Find, and sketch, the particle's potential energy, taking U(0) = 0 (b) Identify and classify all equilibrium points (c) Find the...

I'm looking for a book of classical mechanics. I do not remember the title or the author, but has pictures of this kind, if someone could help me find it would be greatly appreciated. https://dl.dropboxusercontent.com/u/61701794/Captura%20de%20pantalla%20de%202016-09-10%2014-56-03.png...

I am starting a Phd in statistics this year at Montréal University (CANADA). Discussion about physics and quantum mechanics are my interests. THanks to all!

I'm an avid bike rider and a first year physics student. A couple days ago a friend of mine told me about how his friend was going downhill on her bike, used her front brake, and went over. I would like to determine what the minimum speed for a given slope angle is for the biker to do a full...

Homework Statement Two cardboard boxes full of books are in contact with each other on a friction less table.Box H has twice the mass of Box G. If you push on box G with a horizontal force F, then box H will experience a net force of? 2. The attempt at a solution Let book G's mass be = m...

Hello All, I have a question for which I'd like an authoritative answer, if some physics genius would be so kind. I'll try to provide as much background as I can but follow up questions for clarity are more than welcome! So I'm working on the design for a patent application and it involves a...

In the attached picture, can I say that there is a lift force in the Y-direction, and a drag force too in the same Y-direction? FL proportional to V_fx2 ? FD proportional to V_py2 ? Is this equation of motion for the Y-direction correct here: ma = − mg − FD + V(rho)g + FL The lift force is...

Homework Statement Suppose we have a folding ladder, so that when its legs are spread it makes an isosceles triangle. Suppose it has a support that runs parallel to the ground. There is a bucket of paint that rests on top of the ladder, and the mass of the ladder is negligible. Data: The legs...

Homework Statement Block 1 (mass 2 kg) is moving rightward at 10 m/s and block 2 (mass 5kg kg) is moving rightward at 3 m/s. The surface is frictionless, and a spring with spring constant of 1120 N/m is fixed on the left side on block 2. When the blocks collide, the compression of the spring is...

Homework Statement We have a mass m at x = 0 attached to a spring with spring constant k which is moving at constant velocity v such that the position of the spring is described by X = l + vt where l is the equilibrium length of the spring. Solve for the motion of the mass. Homework...

The question asks: Uranium nuclei are unstable and decay by emitting a helium nucleus, which contains two protons and two neutrons. Suppose the original nucleus has 92 protons and 146 neutrons before it emits the helium nucleus, and that the helium nucleus has an knknown speed as it departs from...

Homework Statement A bob of mass m attached to an inextensible string of length l is suspended from a vertical support. The bob rotates in a horizontal circle with an angular speed ω rad/s about the vertical. About the point of suspension : (1) angular momentum changes in direction but not...

Homework Statement [/B] A rod of mass m is attached on the ceiling inside a cart of mass 6m kept at rest. Length of rod is L. Find the velocity of rod with respect to cart when the rod becomes vertical after releasing it. The rod is free to rotate about its point of suspension. Homework...

I am a noobie and I am not really sure this is the right forum to post to, so please excuse me if I am posting in the wrong place. I had considered General Physics and Classical Physics, but I hope I have made my best choice and I don't think it is acceptable to post in more than one forum...

Hello I am in the first year civil engineering course, we are currently learning mechancis. However, I don't get the concept of plane symmetry and symmetrical of forces in 3d problem. so, what's the condition or requirement for symmetry? for the first photo, 1 and 2 are symmetrical about the...