Rod Definition and 1000 Threads

I am given a rod with mass per unit length \mu , cross sectional area A, and under a tension F. I am also told that the tension F is uniform over the cross sectional area A. Find the stress energy tensor inside the rod. I know that for the stress energy tensor T^{00} gives the energy...

Homework Statement A rod of length L and total charge Q is a distance D from a point charge q which lies along the perpendicular bisector of the rod. Find the force of the rod on the point charge Homework Equations E = ∫ dE dq = λdx F = qE The Attempt at a Solution I'm...

Homework Statement I'm currently reviewing some of the old E&M material that I haven't seen in a while and have gotten stuck on this problem. I'm sure I'm just making a simple mistake but I can't seem to make any headway. Here's the problem: Figure 35-32 shows a copper rod moving with...

EDIT: Title should say "To what maximum angle, measured from vertical, does the rod rotate when hit will a ball?" Did not see that it had cut off. Sorry. Homework Statement A 78 g, 40-cm-long rod hangs vertically on a frictionless, horizontal axle passing through its center. A 14 g ball of...

Homework Statement A homogeneous rod with even thickness has mass M and length L. a) Find the gravitational field g(x) at a distance x from the rod on an axis normal to the midpoint of the rod. b) Find the gravitational field g(y) at a distance y from the rod's midpoint on an axis through...

Homework Statement A spring has one of its end connected to the ceiling and the other end connected to the end of horizontal rod. The rod is free to rotate in xy-plane about its vertical axis. The mass of the rod is 0.6 kg and the spring constant is 2000 Nm. If the rod is displaced and...

Homework Statement A thin rod extends along the x-axis from x= +b to infinity. It has a non-uniform linear mass density of A/x^{4} where A is a constant with units of kg m3. Calculate the moment of inertia of the rod for rotation about the origin. Homework Equations The Attempt at a Solution...

Homework Statement This is a problem about angular momentum and torque from the physics textbook Don't Panic Volume I. Attached is a screenshot of the problem. Homework Equations L = mr2ω The Attempt at a Solution The angular momentum must be conserved to keep ω constant...

I was wondering what the difference in current is if there is one when you have a bundle of copper wire passing through alternating magnetic fields verses a solid copper rod of the same diameter. Will the rod have more current because there is more copper? Would it have less because more copper...

I want to ask why a rod's rotational inertia with rotational axis at its end is not 1/2 mR2 but 1/3 mR2?

Okay, so I'm studying for a Mechanics of Materials final at the moment, and I am reviewing the chapter on torsion. I was reading through the given formulae, and I stumbled across one that I could not fully visualize (or simplify): the formula for gamma. Based on my understanding and from...

Homework Statement There is a rod of length L pivoted on one end. It is originally at rest horizontally then released. When vertical, an impulse is applied to bring the rod to rest. Throughout the question I have worked out I = 1/3 mL^2 w= √(3g/L) at the vertical position and an...

Homework Statement A rod whose CG divides it into two portions of length a and b rests inside a smooth sphere in a position inclined to the angle θ to the horizontal. If 2α is the angle it subtends at the centre of the sphere, prove that tanθ= (b-a)/(b+a) tanα Picture is attached...

Let's say there is an elastic collision b/t a particle and a rod. The rod (initially motionless) is struck by the particle at some distance below its CM and particle comes to rest. So we have an elastic collision where v of particle is completely transferred to rod. BUT how do I analyze...

Homework Statement A uniform rod is supported by two strings. The string on the left hand side is horizontal. The string on the right hand side is at 30 degrees with respect to a straight line going from the end of the bar to the ceiling. If you had a straight line going from the end of the...

Homework Statement A non uniform rod of length L=1m and linear mass density: λ(x)=λo(1-(x/2L)) with λo=1Kg/m. It is supported at it's midpoint and initially tips over so that it's left end lies on the ground. Part a: Find the position of the centre of mass along the rod when it is in it's...

Homework Statement Same problem as in https://www.physicsforums.com/showthread.php?t=589704 but instead of a spherical shape, consider an infinite line of constant charge density \lambda _0. Homework Equations Given in the link. The Attempt at a Solution I assume Phi will be the...

Homework Statement Q A cylindrical steel shaft of radius 2cm and long is turned upside down on a lathe to one half its radius for a distance of 20cm from one end find the distance of its centre of gravity from the thicker end.? Homework Equations The Attempt at a Solution

A long, thin rod of mass 9.65 kg and length 10.18 cm is standing stright up on a table. Its lower end rotates on a frictionless pivot. A very slight push causes the rod to fall over. What is the speed of the tip of the rod as it hits table? What is speed of center of mass of rod? 1/2 m...

Homework Statement http://desmond.imageshack.us/Himg339/scaled.php?server=339&filename=53171696.jpg&res=medium Homework Equations GPE = mgh, EPE = λx^2 / 2l The Attempt at a Solution I'm taking the horizontal line through A as the zero-level for potential energy. Clearly, the...

Suppose I have a metal rod in empty space with a uniform mass distribution. Suppose a force acts perpendicular to the rod at some distance R from the rod's centre of mass over some time Δt. There are no other forces acting on the rod. (1) What type of motion will the rod have over Δt? Will...

Homework Statement A clock’s pendulum is 60 cm long with a bob at the end of mass 500 g. Determine the maximum tension in the pendulum rod when the bob is b) swinging at a speed of 2.4 m/s Homework Equations v^2 / r = ac The Attempt at a Solution 9.8m/s^2 = g (2.4)^2 / 0.6 = 9.6m/s^2...

Hi Everyone, I have a question about panel vs. solid rod structures. Assume a two cubes of equal dimension and weight. Cube 1 is made of panels, ie. a hollow cube. Cube 2 is made with solid rod Material is linear elastic Which would be stiffer? I think the panel...

Let us say we have a very long glass that has a uniform square cross section. Its long axis is aligned with the x axis. A beam of light is directed along the y-axis such that it is normal to the side of the glass rod's side surface. When the rod is stationary wrt to the observer we would expect...

Hi: I have a tank of water (of plastic) of about 2 x 4 feet. I want a steal rod (with a ball of 5 inch at end of rod) to be cross that water tank from center, but water should not leak from tank (rod will enter from right and exit from left of tank) You can get more idea from image that...

Homework Statement A uniform rod AB of weight W rests in equilibrium with the end A in contact with a smooth vertical wall and the end B in contact with a smooth plane inclined at 45 to the wall. Find the reactions at A and B in terms of W. Homework Equations The sum of the three forces equal...

When an induced emf is created in a conducting rod why is the resulting potential higher at the positive end of the rod? Since the electrons accumulate at the negative end of the rod then wouldn't this be the higher potential instead? Don't negative charges flow from lower to higher potential?

Homework Statement A thin charged rod of length L lies along the x-axis as shown in the diagram below. The charge on the rod is distributed with a density of λ= c x (C /m) where c is a constant. What is the potential at a point (0,y)? (Your answer should be in terms k, c, L, and y). See...

So Imagine that a force of 100 N is being applied continuously on face of 5 kg cylindrical rod (1 light year across) causing it to accelerate at 20 m/s^2. If the force was abruptly removed would the rod continue to accelerate a noticeable period of time before coming to a halt? The density of...

Homework Statement A rigid rod has rest length L0 and moves relative to a system S' for which it's coordinates is x'=0, y' = b-ut', z' = 0. In this reference frame the rod is at all times parallel with the x'-axis. a) A point (A) on the rod is measured to be a distance= a, away from x' = 0...

Homework Statement GRAVITATIONAL POTENTIAL AND FIELD DUE TO A “THIN” ROD A thin rod of length L lies along the +y-axis, with one end at the origin (see diagram). Assume: • The rod has length only- no thickness in other directions. • The density of the rod increases proportionally to...

Homework Statement Let a rod with length L and constant cross-sectional area A have the density ρ(x) = ρ((3.x^2 + 2.x.L)/L^2) 0 ≤ x ≤ L where x is the distance from one end of the rod and ρ0 is a real constant. (a) Find the total mass M of the rod. (b) Find the x-coordinate xc of...

For a rod magnet, how is the field inside the rod change if another piece of ferro magnetic material is being brought close to one end of the rod? Does the presence of ferro magnetic material increase the field strength inside the rod magnet?

Homework Statement Suppose there is a rod on a friction less horizontal plane and an impulse "J" is given to it at a distance "x" from its center. Using this data I have to find out the instantaneous center of rotation. The Attempt at a Solution By impulse-momentum theorem, J =...

It is told, that all homework-like threads should be posted there. So, here I go. Imagine such a situation: there is a vertical rod and a cylinder, with the hole diameter sightly larger than the diameter of rod. There is also a second rod, attached to the cylinder perpendicularly. There is a...

Imagine such a situation: there is a vertical rod and a cylinder, with the hole diameter sightly larger than the diameter of rod. There is also a second rod, attached to the cylinder perpendicularly. There is a friction between the main rod and the cylinder. It is known, that if we put a...

Homework Statement Thin Rod - Length = 5.0cm - Total Charge = 8.4 nc Calculate the electric field at point p, 3cm away. Homework Equations E = (1/4∏ε) * (q/r^2) λ = Q/L The Attempt at a Solution I think you treat the rod as a series of point charges, meaning the electric...

I need to calculate the force necessary to bend a rod 180 degrees around a radius of 1.75 meters. Basically bending the rod into a horseshoe. I have looked at the simple bending calculations and I am sure this must be similar to those but I do not see anything for a constant radius bend. Any...

Homework Statement Infinitely long rod with the z axis at its center. The rod has a uniform mass per unit length \mu. Find the gravitational force vector F on a mass m, at a distance \rho from the z axis. Homework Equations F=-G*(M*m)/R^2 (times radial unit vector rhat for the vector form)The...

Homework Statement A uniform thin rod with mass M and length L nailed by frictionless pivot can swing freely on the wall as shown in Fig. The pivot locates at the distance L/4 from the bottom and stops inside. The velocity of the bullet before hitting the rod is v. (a) Compute the max. angle...

What happens? I think nothing should happen since the rods will not get magnetised at all due to the ac current.. Thanks for the help!

Homework Statement A thin rod of total length L has a nonuniform density given by λ(x)=ae^-bx where x is distance from one end of the rod. What is the moment of inertia of the rod for rotations around the end at x=0. Measuring from x=0 to x=L Homework Equations λ(x)=ae^-bx...

I am not sure whether this is the correct section to post in but here it goes... I am really confused as to why the textbook has a "d" in denominator and why their integral is different from mine...I used the integral in 2nd column 2nd row but the textbook is different :S I am not sure why...

Homework Statement one fourth length of a uniform rod of mass "m" and length "l" is placed on a rough horizontal surface and it is held stationary in horizontal position by means of a light thread. The thread is then burnt and the rod starts rotating about the edge. Find the angle between the...

Homework Statement Determine the equilibrium temperature distribution for a one-dimensional rod composed of two different materials in perfect thermal contact at x=1. For 0<x<1, there is one material (cp=1, K0=1) with a constant source (Q=1), whereas for the other 1<x<2 there are no sources...

Homework Statement An infinitely long, uniformly charged straight line has linear charge density λ1 coul/m. A straight rod of length 'b' lies in the plane of the straight line and perpendicular to it, with its enared end at distance 'a' from the line. The charge density on the rod varies with...

Homework Statement I am looking for the absolute value of the electric field at point A (see picture below) relative to the whole charged rod at the left side.Homework Equations -The Attempt at a Solution I am not quite sure whether my choice for R and the boundaries of the integral are...

Homework Statement A nonconducting rod of length L = 6.00 cm and uniform linear charge density λ = +2.28 pC/m. Take V = 0 at infinity. What is V at point P at distance d = 8.00 cm along the rod's perpendicular bisector? heres the diagram best I could show it: .P...

Homework Statement An infinite sheet of charge that has a surface charge density of 25.9 nC/ m2 lies in the yz plane, passes through the origin, and is at a potential of 1.32 kV at the point y = 0, z = 0. A long wire having a linear charge density of 81.1 nC/ m lies parallel to the y-axis...

I have now finished my lectures on classical mechanics, but I'm a bit ashamed to say that I still don't understand the concept of torque fully. Let's imagine this. We have a rod being acted on by the equal and opposite forces, but in different distances from the centre of rotation (attached...