Center Definition and 1000 Threads

Homework Statement A conductor consists of a circular loop of radius R = 14.4 cm and two long, straight sections as shown in the figure. The wire lies in the plane of the paper and carries a current I = 1.60 A. Find the magnetic field at the center of the loop. Homework Equations...

Homework Statement I am trying to understand a substitution used to solve for the center of mass of a solid uniform hemisphere as in this post: https://www.physicsforums.com/threads/solid-hemisphere-center-of-mass-in-spherical-coordinates.650663/#post-4151797[1] I completely understand the...

what's the center of a globular cluster , is it a star or can it be a black hole ? how are they formed and bound to gravitational pull of the milky way

Homework Statement A total charge Q is uniformly distributed on a thread of length L. This thread forms a semicircle. what is the potential at the center? (assume V=0 at large distances) Homework Equations V = -∫Edl E = kQ/r^2 The Attempt at a Solution V = - ∫Edr = -E∫dr = -Er = - kQr/r^2 =...

Homework Statement [/B] I don't understand what I'm doing wrong with this problem: An old club-ax consists of a symmetrical 8.3 kg stone attached to the end of a uniform 2.9 kg stick. The stick is 98 cm long, and the 18 cm long stone is drilled through its center and mounted on one end of the...

Homework Statement Use Mach’s restatement of Newtonian mechanics to show that if we define the centre of mass of two particles according to, ⃗ r = (m1 ⃗ r1 + m2 ⃗ r2) / (m1 + m2) then the center of mass moves according to the equation, ⃗r = [(m1 ⃗u1 + m2 ⃗u2) / (m1 + m2)]t + ⃗r0 where ⃗r0 is...

Hi everyone, Basic question here. Residential pole mounted transformers and many other transformers that produce a neutral have that neutral "center taped" from a current carrying coil in the transformer and bonded to ground. My question is why doesn't the current in the coil short threw that...

hey there I am doing a lot of center of mass problem most of them with collisions , and most of the solutions I see, have a big part of "trigonometric trciks", like the way u watch the vectors in cm frame and the way in the lab frame. does anyone met this kind of solutions and have some tricks...

On youtube, I came across to one of many videos trying to explain General Relativity. One of the comments was interesting to me: "I understand how gravity causes an object with velocity to go in curves or to orbit, due to the curvature of space-time: the object thinks that it's traveling in a...

hi i am araz a mechanic master engineer and i am looking for any article or information about" Instantaneous Center of Zero Acceleration of Rigid Body" because i couldn't find any but "Instantaneous Center of Zero velocity":confused: i hope here i can find some help?!

Homework Statement A cart of mass m moving at 12 m/s to the right collides elastically with a cart of mass 4.0 kg that is originally at rest. After the collision, the cart of mass m moves to the left with a velocity of 6.0 m/s. Assuming an elastic collision in one dimension only, what is the...

I am sure this topic has not been posted this forum before since it didn't come up in my search. I am preparing for MSc and Integrated PhD (in physics) entrance examinations in India using self study materials. However, I wish to join a good entrance coaching center since there is huge...

Good night! Please, what happens to an object (eg a spaceship) placed exactly in the center of mass of a binary star system (composed by two similar stars)? Would it be compressed by a huge gravitational mass (something like the mass of both stars)? Would it be stretched and torn? Or would it...

The gravitational pull of an object always points toward the center of that, but what makes something an object? If you cut an object in half would each half of the object have a gravitational force toward its center of mass, or would the force point toward the center of mass of the original object?

Is center of mass a vector quantity. If so then how? Is it directed towards Earth's center?

Concerning Quantum Phenomenon: I understand the effects of liquid nitrogen on the magnetic fields. However If you ran a tube of liquid nitrogen in the center of a torus magnet or toroidal inductor - would the magnetic field increase, toroidal magnetic vector potential increase. (Zero-point...

what is the difference between center of mass and center of gravity ? please explain it in an easy way ...

What is the center of inertia? Is it the same as the center of mass?

Homework Statement It is a question I asked to myself because I need to reply to another one. I imagined this case: http://imageshack.com/a/img912/7730/R964Vq.png The step2 needs the energy E1, the step3 needs nothing because the gravity is 0 (I imagine the device between the Earth and the...

I was thinking of the conditions exerted at the center of our Earth. If a man let's say in America falls toward the Center of the Earth and a man on the opposite side of the Earth falls, where would they meet? I read that the gravitation force at the center of the Earth is at 0. If they both...

I am a beginner and this is my first post. We know torque ## \vec T = \vec r × \vec F ## Now, should r be fixed in magnitude? I mean can I calculate torque only if the particle is rotating at a fixed distance around a fixed axis? I am having this idea because torque is explained (from where I...

Homework Statement Two men with masses 70 kg and 120 kg rotate at 1 rpm on a frictionless surface and are attached by a 15 m rope. If they pull the rope so that only 10 m is between them when they rotate, how long does it take to make 1 revolution? Homework Equations Angular Momentum and...

Hi all, I am after some help to find out how to do the following: I have a triangular object (weighing around 40,000kg) which I can measure and weigh. I have 4 load indicators I can position anywhere beneath the object, these will give me a very accurate reading of the weight of the object at...

Homework Statement Suppose that a system consists of several bodies, and that the position of the center of mass of each body is known. Prove that the center of mass of the system can be found by treating each body as a particle concentrated at its center of mass. Homework Equations ## \vec R...

Homework Statement A uniform horizontal beam of length 8.00 m and weight 200 N is attached to a wall by a pin connection. Its far end is supported by a cable that makes an angle of 53.0 degrees with the horizontal. If a 600-N man stands 2.00 m from the wall, find the tension in the cable and...

Homework Statement Find the center of mass of an equilateral triangle with side ##a## Homework Equations ## \vec R = \frac{1}{M} \int \vec r \ dm ## ## dm = \frac{M}{A} dx dy ## ## A = \frac{\sqrt{3}}{4}a^2 ## The Attempt at a Solution I set a pair of orthogonal axis ##(\vec x,\vec y)##...

If an object that has more mass at one end of it was dropped, how come the heavier end would be facing closer to the ground than the lighter end? For instance, a toliet plunger is dropped, and the heavier, rubber end of it positions itself at the bottom during the fall. What is this called?

Hello everyone! New member here, as an ME major I always seem to come across very valuable information here, so I figured I would see if possibly someone here could help me. The problem I am dealing with involves modeling a car through certain motions such as hitting a speed bump, and part...

Homework Statement Find the x-coordinate of the center of mass of the lamina that occupies the region cut from the first quadrant by the lines x = 6 and y = 1 if the density function is p(x,y) = x + y + 1 Homework Equations Mass = ∫∫spdσ X Coordinate of center of Mass = Myz/M Myz = ∫∫sxpdσ...

Hello all, this is my first post here. I will try to phrase it as best I can, my physics background is weak, so please be patient, and thanks in advance for your help! I tried researching simple pendulums but couldn't quite find an answer. Suppose a person is suspended, prone, from a pendulum...

A uniform rod of length 2L and mass 2m is bent on its center at a right angle. The rod hangs down from the ceiling using a thread, so that one part, AB, is horizontal, and the other part, BC, is vertical. The question is what's the distance (x) between the suspension point D to the point A (the...

Homework Statement Let ##G## be a group such that its center ##Z(G)## has finite index. Prove that every conjugacy class has finite elements. Homework EquationsThe Attempt at a Solution I know that ##[G:Z(G)]<\infty##. If I consider the action on ##G## on itself by conjugation, each...

Homework Statement Homework Equations v = rw The Attempt at a Solution I am not sure where to begin, honestly. For part (a), the angular velocity w will be v/r for the lower tire and upper tire both so all I need is the right values of v and r. Now for r, what is the reference point...

Problem Statement: Moe Mentum and Ken Ettik are playing pool. Moe hits the cue ball, sending it towards the 6 ball at 2 m/s. It strikes the stationary 6 ball off-center, moving off at a 60 degree angle from the original direction after a perfectly elastic collision. Both balls have a mass of...

Homework Statement In Fig. 29-71, a long circular pipe with outside radius R = 2.6 cm carries a (uniformly distributed) current i = 8.00 mA into the page.A wire runs parallel to the pipe at a distance of 3.00R from center to center. Find the (a) magnitude and (b) direction (into or out of the...

Homework Statement The center of a 1.00 km diameter spherical pocket of oil is 1.00 km beneath the Earth's surface[/B]. Estimate by what percentage g directly above the pocket of oil would differ from the expected value of g for a uniform Earth? Assume the density of oil is 8.0*102 kg/m3...

Homework Statement Imagine a giant star, lit with twinkly lights for the holiday season. Are you interested in the magnetic field at the center of the star? Sure you are. The star has “arm” length (AF) equal to 1 m and 1 amp flows clockwise around the star. 1. Find the following lengths: BG =...

So here's my problem: The distance between two stars is constant(d = 4,3 * 1010m), and they have a common center of mass. Ms = mass of our star, ma = 0,82 * Ms and mb = 2,2 * Ms. What I'm supposed to do is calculate the period of orbit of both stars, which is the same for them both, since the...

Greetings, Here is my question: What is the difference between the labframe and the center of mass frame in QM scattering theory? Is it that in the labframe both particles are moving towards each other and in the center of mass frame one particle is static and a second one is moving towards the...

Homework Statement A club-axe consists of a symmetrical 23.0 kg stone attached to the end of a uniform 2.8 kg stick. The length of the handle is L1=91.0m and the length of the stone is L2=13.0cm. How far is the center of mass from the handle end of the club? Homework Equations Center of mass...

In many vortex's, the center has low pressure, from the center of a stirring cup of tea to the centere of a hurricane or storm system. I'm trying to crudely model how this might apply to the center of a spiral galaxy. If the behavior is similar, and the center has a low pressure void...

Homework Statement All three disks are made of sheet metal of the same material, and the diameters are 1.2m ,2.4m , and3.6m . Assume that the x-axis has its origin at the left-most point of the left-most object and it points to the right. A) Determine the location of the center of mass of the...

Homework Statement Three beads are placed on the vertices of an equilateral triangle of side d = 1.8 cm. The first bead of mass m1 = 150 g is placed on the top vertex. The second bead of mass m2 = 55 g is placed on the left vertex. The third bead of mass m3 = 85 g is placed on the right...

Hi, I checked the forum rules and homework / coursework is not allowed so I am not sure if this is appropriate or not. Feel free to guide me through appropriate forum and/or lock this thread if such questions are not allowed. The question I have is mostly related with my research and since I am...

Hi. There are two masses connected by a massless bar, and from the unstable equilibrium position shown in the figure is slightly inclined so it falls down, being the final state of the system that both masses are in contact with the surface. There is no friction between the floor and m2. The...

Homework Statement A thin rigid rod of length ##l## is placed perfectly vertical on a smooth ground. A slight disturbance on the upper end of rod causes lower end of rod to slip along the ground and rod starts falling down. Find velocity of center of mass of rod when the rod makes ##30## with...

y/SUB]Homework Statement Determine the electric field at the center of the triangle. All sides are 15.6 cm. Vetex is 2.0 uC (Q1) while the bottom points are both -4.0 uC (Q2 and Q3). Homework Equations E = kQ/r^2 E = F/q The Attempt at a Solution Ecenter = E1 + (2)E2 = ? First calculate...

Homework Statement Suppose a grounded spherical conducting shell of radius R surrounds a pointlike dipole at the center with \vec{p}=p\vec{k} Find the potential V(r,\theta) for r <= R. Hint: Use spherical harmonics regular at r=0 to satisfy the boundary condition. Homework Equations General...

Homework Statement Use energy conservation to answer the following question. A mass is attached to one end of a massless string, the other end of which is attached to a fixed support. The mass swings around in a vertical circle as shown. Assuming that the mass has the minimum speed necessary at...

I am working on an algorithm which requires the coordinates for the center point of an offset circle. Dimensions available to find this are shown in the image below and the dimension required is labeled as X: The point at the very left of the arc is a quadrant therefore, the circle center also...