Angular Definition and 999 Threads

Homework Statement Gear 2 in the figure below is driven at a speed of 80 rpm in the CCW direction viewed from the right end. Gear 4 meshes with a fixed ring gear (gear 7) and with gear 5. Find the angular velocity of gear 5. N2= 16 T, N3= 32 T, N4= 30 T, N5= 22 T and N7= 77 T. Homework...

ηϖ1. Homework Statement Homework Equations I=½MR2 PE=mgh The Attempt at a Solution The first thing that jumped out at me was "uniform cylinder" so I went ahead and calculated the moment of inertia for the cylinder and got I=½(4.4)(.4)2 = .352 and held onto that. Then, I calculated the...

Homework Statement http://imgur.com/koz4PpI Homework EquationsThe Attempt at a Solution I was able to calculate the net torque on the pulley as 55.88 and the Inertia as .352. Those could be wrong, but that's as far as I could get. I really have no idea. Any kind of help/explanation would be...

In the image above, a centroid with radius 1 is depicted. F1 is pointing directly at point A (which is the center of the circle), and F2 is pointing directly at point B. The radius for finding the torque would be the perpendicular between the center of the object and the force vector, so r1...

Homework Statement https://holland.pk/uptow/i4/ae8d3da6c3ce3cad10eb98dd3208a955.png Homework Equations τ=I⋅α The Attempt at a Solution I want to discuss in part (a) of the question Tension in 5 kg block string=mg=5*9.8=49N Taking moment at the pivot, a net torque acting on 15 kg post is...

OK, I understand that 'spin' is just an unfortunate name some someone gave to a particular quantum property and that particles do not actually spin. I also accept that I may never be able to understand what spin is without also understanding the mathematics involved. However, I am also told...

Hi Folks, Problem Statement How would one use the conservation of angular momentum to explain the attached picture? The rod is held fixed horizontally..the person holds on to the cork and then let's go...apparently the glass is saved due to this conservation... Relevant Equations Momentum...

Hi Folks, How would one use the conservation of angular momentum to explain the attached picture? The rod is held fixed horizontally..the person holds on to the cork and then let's go...apparently the glass is saved due to this conservation...

Homework Statement a spool of radius R1 and R2 (R2>R1) is kept on hortizontal surface. A force f= 2t N (where t is time ) acts on the inner radius tagentially find the angular momentum of the system about the bottomost point of the spool. Homework Equations v=u+at W=Wi+alpha(t) L=IW+mvrThe...

Homework Statement A uniform rod of length L and mass M hangs at rest from a frictionless pivot. The rod is hit a distance 0.8L below the pivot by a particle of mass m moving perpendicularly to the rod at speed v; the particle sticks to the rod. Following the collision, the maximum angle...

I am currently trying to model collisions of rigid balls. I have successfully been able to calculate collisions that only deal with linear momentum, but have run into trouble when I want to calculate angular momentum (e.g. when ballA glances the top of ballB, both balls should start spinning a...

Homework Statement A hydrogen atom is in the 3d state. Determine the orbital angular momentum. Homework Equations unnecessary The Attempt at a Solution I already know how to figure this out and have an answer but WHAT ARE the units?! It's not kgm/s^2!

Homework Statement A speed skater increases his speed from 10 m/s to 12.5 m/s over a period of 3 seconds while coming out of a curve of 20 m radius. a. What is the magnitude of his angular velocity as he leaves the curve? Be sure to include proper units for your answer. b. What is his average...

Hi guys, This is basically a quick question to hopefully find some pointers on a topic I've been browsing the internet on to not much success. Basically the topic I'm trying to find more information on is the angular momentum problem with the "nebular hypothesis" of the formation of our solar...

Homework Statement In the mechanism shown below, the angular velocity of link 2 is 17 rad/s CW, constant. Find the angular velocity (magnitude and direction) of link 3. The distance between A and C is 109 mm, the length of link 3 is 125 mm, and θ= 111°. Note: B is a pin-slider In the...

Comets travel around the sun in elliptical orbits with large eccentricities. If a comet has speed 2.0×104 m/s when at a distance of 2.6×1011 m from the center of the sun, what is its speed when at a distance of 5.2×1010 m . Express your answer using two significant figures I applied...

Homework Statement A mass "m" is attached to a spring of constant "k" and is observed to have an amplitude "A" speed of "v0" as it passes through the origin. a) What is the angular frequency of the motion in terms of "A" and "v0"? b) Suppose the system is adjusted so that the mass has speed...

Homework Statement A particle of mass ##m## rotates about ##Z-##axis in a circle of radius ##a## with a uniform angular speed ##\omega##. It is viewed from a frame rotating about the ##Z-##axis with a uniform angular speed ##\omega_0##. Find the centrifugal force on the particle. Homework...

Homework Statement The nucleons in a nucleus have a net orbital angular momentum ##L = 1## and spin angular momentum ##S = \frac{1}{2}##. What are the possible values of the total nuclear spin ##J##, i.e. the total angular momentum of the nucleus, and what are the possible values of ##J_z## in...

I don't typically do this, but attached is a figure with a problem statement. This is not homework because I have already solved it! My question is a subtle one. Please see the attachments, one is the question and the other is my solution. I know my solution is correct, but at the end of...

m1v1 = m2v2 v = rω m1(rω)1 = m2(rω)2 m1ω1 = m2ω2 Does this make sense?

The "color force" doesn't actually change the color of quarks because they don't actually have any color. We use the word "color" non-literally here. Now, I'm told that quarks don't "actually" "spin" either, so again, I infer that it's a term used out of convenience, but I'm also told that they...

In 1-dimensions, the final orientation after undergoing constant angular acceleration is: \theta_f = \theta_0 + \omega_0 t + 0.5 \alpha t^2 What is an analogous equation in the 3D case? In other words, if I know the initial orientation (say, as a quaternion), angular velocity (as a 3-vector...

Is this a legitimate equation? θ'' = − g⁄R sin θ Source: ftp://www.myphysicslab.com/pendulum1.html ftp://www.myphysicslab.com/images/pendulum_2.gif The pendulum is modeled as a point mass at the end of a massless rod. We define the following variables: θ = angle of pendulum (0=vertical) R =...

Suppose you have a ball on a string, and you make the ball to move around in a circle. The force on the ball is caused by the tension of the string, and is called the centripetal force F = mv^2/r. If you were to let go at any moment, the ball would stop rotating and move with linear velocity...

My textbook talks about the average angular speed that ω = angular displacement / time for the angular displacement to take place. So the question is like there is m1v1 = m2v2, can the velocity be instead average angular speed to have the conservation of momentum equation like this? m1ω1 = m2ω2

Homework Statement A sprinter runs the curve of this 200 m in 12.96 s. Assume he ran in a lane which makes a semicircle (r = 36.8 m) for the first part of the race. At 3.36 s into the race his speed is 5.1 m/s. At 7.6 s into the race his speed is 9.6 m/s. His speed after the curve was 11.1 m/s...

Homework Statement A particle is attached by means of a light inextensible string to a point 0.4 m above a smooth horizontal table. The particle moves on the table in a circle of radius 0.3 m with angular velocity ω. Find the reaction on the particle in terms of ω. Hence find the maximum...

I've been asked to replace a professor for a couple of classes in an undergraduate quantum mechanic course. I have to present some topics on angular momentum, including the addition of angular momentum. I have no problem with the general theory and can present it just fine. But I would like to...

Hello, I need some help regarding angular physics. I am working on a project and I want to be able to predict (to some degree) the velocity of the payload leaving the trebuchet. (Excuse my ignorance I am just a high school student) Lets say a trebuchet see diagram has a counter weight m1...

Hi all, I got a feeling that learning quantum mechanics is easy and hard. Most of time, it is easy to "accept" all the concepts given in the book by simply looking at their mathematical interpretation. But it is hard if you really take it serious to try to understand everything from the...

Homework Statement We have a concrete mixer, and if the drum spins too fast, the ingredients will stick to the wall of the drum rather than mix. Assume that the drum of the mixer has radius R = 0.5 m and that it is mounted with its axle horizontal. What is the fastest the drum can rotate...

Homework Statement A 500.0-g bird is flying horizontally at 2.25 m>s, not paying much attention, when it suddenly flies into a stationary vertical bar, hitting it 25.0 cm below the top(Fig. P10.85). The bar is uniform, 0.750 m long, has a mass of 1.50 kg, and is hinged at its base. The...

Homework Statement Particle is in a state with wave function \psi (r) = A z (x+y)e^{-\lambda r}. a) What is the probability that the result of the L_z measurement is 0? b) What are possilble results and what are their probabilities of a L^2 measurement? c) What are possilble results and what...

This (photo) is a very typical example of conservation of angular momentum, but my trouble arrises from trying to prove that the difference of energy will have to correspond to work, by calculating the work done by you to alter the moment of inertia. I have spent a lot of time in this, but I...

I've been reading a book that talks about the angular momentum of an extended body around a point 0 (H_0) being made up of the moment-of-momentum of an equivalent particle (representing the total mass at the centre of mass) with respect to the point 0 and the angular momentum around the centre...

Hi there guys. I'm new here, and I'm learning physics by myself. Please, if the answer to my question is too obvious, be kind hee hee, I'm a 13 and trying to learn physics by myself. So, I know that we have ## \textbf{L}= \textbf{r} \times \textbf{p} ## Then, we can write ## \frac{d}{dt}...

Homework Statement Counter clockwise is positive, right is positive and up is positive. My problem statement: When I use the formula ag = alfa*r do I have to take signs into account? Or is this formula just for the magnitude and will the signs be already taken into account in other equations...

Homework Statement I have chosen my axis as you can see on the picture. To the left, it is the positive 'r'-axis, up is the positive 'y'-axis. I have to calculate the angular speed. My solution is correct, but I'm getting into trouble at the end. I have to take the roots of the last equation to...

Hello everyone! I have a problem , to which I do not understand the law of conservation of angular momentum... I searched this problem on the web and it is obvious that I am making the mistake. So we have a rod of length ##L## and mass ##m## that is lying on a horizontal frictionless table. We...

This is from text [Introduction to Lagrangian and Hamiltonian Mechanics] on NTNU opencourse. Annnnd... I don't use english as my primary language, so sorry for poor sentences. I can't get two things in here. First, at (1.12) I can't understand how L dot derivated like that. Since I know...

To calculate the Keldysh parameter, I need to use the optical frequency of a laser in atomic unit. Since for the time: 1 a.u. = 2.42×10-17 s, I would assume that for the frequency: 1 a.u. = 4.13×1016 s-1 which is juste the inverse of the time one. However, I found several sources such as...

Why is the term ##(\sin\theta\,\dot{\theta})^2## fourth order in the small ##\theta##, as claimed by the sentence below (5.108)? By small-angle approximation, ##(\sin\theta\,\dot{\theta})^2\approx\theta^2\,\dot{\theta}^2##. For this to be fourth order, it seems like we must have...

Hello! I'm trying to derive the linear velocity vector from the position vector and the angular momentum vector. I've seen on the internet that V = W x R (V,W and R are all vectors and x is the cross product) but I cannot for the life of me derive it! I've tried doing it by writing out the...

I know that magnetic fields can align objects with spin. In that case, if we suspend an object and turn on a magnetic field such that a significant number of electrons become aligned with the field, could we observe a macroscopic change in angular momentum?

Homework Statement The orbit of an electron (-e) around a nucleus (Ze) is a circular orbit of radius a in a plane perpendicular to a uniform magnetic field \textbf{B}. By writing the equation of motion in a frame rotating with the electron, show that the angular velocity \omega is given by one...

Homework Statement You connect a light string to a point on the edge of a uniform vertical disk with radius R and mass M. The disk is free to rotate without friction about a stationary horizontal axis through its center. Initially, the disk is at rest with the string connection at the highest...

Homework Statement The potential energy of a particle of mass m is V(r) = k/r + c/3r^3 where k<0 and c is a small constant. Find the angular velocity \omega in a circular orbit of radius a and the angular frequency \omega' of small radial oscillations about this circular orbit. Hence show...

Homework Statement How do you calculate instantaneous angular speed?[/B]Homework Equations I have been told that it is when delta t approaches 0, so its just the derivative of delta theta over delta t.[/B]The Attempt at a Solution does it involve tangent line like normal instantaneous...

Hello. The quantum mechanics textbook shows the relation of J1 + J2 + J3 ≠ J1 + (J2 + J3). I believe Ji is total angular momentum operator for ith group of electrons (but actually I have not seen J1 operator while I have seen J12 operator so far). I don't know how to prove J1 + J2 + J3 ≠ J1 +...