Rod Definition and 1000 Threads

Two professors had a discussion one physician and the other eletrical engineer. The first one sad that during a experiment he observed a lightning rod avoiding any discharge, saying that lightning rods when well grounded should avoid discharges and not attract then. The engineer sad that...

I am saying that V1=V2 since the emf induced in the rod is the same for both cases equal BLv. Am I correct?

By looking at the following question, I have no idea why the direction of force exerted by rod on a ball is represented like that. can anyone help me to understand?

I tried to solve the problem like this. 4-1. m d/dt (v_1) = mg sin(theta) - F 4-2. m d/dt (v_2) = R - mg cos(theta) If there is no slip, v_1 = v_2 = 0, so F= mg sin(theta), R= mg cos(theta). In the rotational motion equation, we intergrate 5-1. I omega^2 = 2dmg ( sin theta_f -...

Hi! I am a high school physics teacher in Korea. I have a question for you, a physics expert. A rod that falls while rotating from the end of a table A rod of mass m and length L is inclined by theta o (thera_o > 0) when the center of the rod is in contact with the end of the table, and the...

I would've thought such a thing exists, but I can't find any. Have you heard of something like this...? A simple extending telescoping rod, but it is airtight, and at one end, the cylinder can be closed or opened by the user to respectively lock the rod in position, or allow it to...

TL;DR Summary: A thin piece of spaghetti of diameter d is balanced horizontally from its middle. It can have a length ℓ ≫ d before it snaps under its own weight. How does ℓ scale with d? Let the spaghetti rod have density ρ, and consider ONLY its right half. (1) The spaghetti rod experiences...

I will present the case as an exercise because I believe it will be easier to understand that way. I didn't know if I should post it under the mechanics or electromagnetism sections because I am actually trying to link both. Since it feels like a fairly simple problem, I considered the Classical...

A rod of length 'L' is hinged at one of its ends and is lying on the ground. A torque 'T' is applied to it at the hinge such that it pushes the rod into the ground. What will be the force profile on the ground since the entire length of the rod touches the ground? Assume the rod is weightless.

OA*P_A = OH*P + OB*P_B ⇔ OA*P_A = ¾*OA*P + 2OA*P_B ⇔ 5*10 = ¾*0.4*10 + 2*P_B →P_B=23.5 →m2=2.35 (kg) My result doesn't match the answer hint, and when I change the rod's centre of mass to OH=1, it fits the answer hint. How do I determine the centre of mass in this situation?

so I need to use the eq.: omega_pr = ##mgr / L_s## with r = 6cm. But from how I imagine/see it, the rod pierces the disk through the middle so how does this create precession if the weight will not cause a torque then and thus a hortizontal change in angular momentum? Thanks in advance!

so calculated, the moment of inertia for a rod about an axis at the end of the rod is I = 1/3 * M * L^2 here for case 1: arms to the side I is calculated to be ##I = 0.224## for case 2: arms stretched ## I = 1 / 3 * M * L^2 + M * d^2 ## with L = 0.6 m (length of rod) and d = 0.2 (dinstance from...

I was able to solve first part I.e. time period of the system when bearing has friction I am unable to figure it out why disk will not rotate when it is mounted to frictionless bearing ? I know that due to absence of friction disk cannot rotate but then Mg is also there which can rotate the...

On question B, I've attempted a solution that I have posted. However, I don't think it's correct. Am I allowed to treat this rope that wraps around the rod as a "negative" force and simply attach it to the other side of the equation such that ## m_1g=m_2g+\mu_sN##?

The question is: A uniform rod of length ##L## stands vertically upright on a smooth floor in a position of unstable equilibrium. The rod is then given a small displacement at the top and tips over. What is the rod's angular velocity when it makes an angle of 30 degrees with the floor, assuming...

Hey Im doing FEA and got stuck on question. The diagram go me stuck, because looking through the workbook it says high stresses are in red and low in blue, whereas they included both different kind of stresses on the same diagram and no data. Note: High Compressive strains are noted by blue...

I tried to draw a free-body diagram and sum of moments equal to zero, but I stuck there, because I don't know where should reaction force N be and how determine where friction is acting on round surface? Any ideas?

Ideally, it should look circa like this: But in reality, it looks often like this: Is the formula valid also in this case?

For this problem, Why for part (a) the solution is, Is the bit circled in red zero because since the putty is released at a very small distance above the rod it velocity is negligible? Also for part (d) the solution is I did a computation of the initial and finial kinetic energies of the...

For this problem, However, I am trying to solve this problem using an alternative method compared with the solutions. My method is: ##\vec E = k_e \int \frac {dq} {r^2} \, dx ## ##\hat r## ##\vec E = k_e \int \frac {\lambda} {x^2 + d^2} \, dx## ## \hat r## If I let ## \hat r = \frac {-x\hat i...

I like this idea. Very creative, but in retrospect it sounds obvious. Just create a path of ionized atoms.

I'm sorry I'm uploading lots of images because I don't know how to write equations here. PROBLEM DESCRIPTION I have to solve this problem: Figure P3.6: MY SOLUTION I did this: THE CORRECTION I got this as a correction: - Don't use the middle line in figure P3.6 in my calculations. -...

hello guys, I wanted to ask whether I can just consider/think about this as being rotation around a fixed axis in a plane representing it as if it was 'just' a rod. This is mainly so that for the kinetic energy in the second position is where if we think about it in just a plane. Is this...

The doubt is about this question. Which the answer is They say that all the forces are pulling forces? How is this the case? How would this setup even work? I don't think block 2 could pull the rod.

Hello, id appreciate your help for the following case: in a room, a zero weight rod has zero friction bearings at its extremities. One of his ends lies on the floor, the other is against a wall, forming with it an angle alpha. A verical force fv is applied to the 'wall end'. How to calculate the...

Two point-like particles of mass m. The particles are rigidly connected to each other with a mass-less rod of length L. The particles are initially at rest in such a way that one particle is at the origin and the other is at the point (0, L). A point-like particle of mass M collides with a...

I want to make a few of these if it will not cost a lot.

The net torque about an axis through point A is given by, If I take the axis of rotation perpendicular to the paper and the solution I arrive would be the following below Net torque = 30 cos45 x 1.5 - 10 cos30X 3 = 5.829Nm ( counterclockwise) But the book gives an answer...

I suppose it can shield only the external magnetic field, not the field of the magnet itself. But I am not completely sure.

I suspect we can treat the L shaped rod as two rods and then find the com for that system and then find the com of the ball and that system

hello i would like to understand to something. here is the drew now for my question: i was able to find Ey and here is my correct answer: when i try to find Ex i didnt understand something, i found the correct answer but i need to put minus before and i want to know why? here is my solution...

Figure: Attempt at a Solution: $$F=k\Delta x=lk\sin \theta$$ $$\delta x=0 \quad \textrm{when} \theta=0$$ $$\sum M_C=0\rightarrow$$ $$\rightarrow Pl\cos \theta -F_yl\cos \theta -F_xl\sin \theta =0\rightarrow$$ $$\rightarrow Pl\cos \theta -Fl\cos^2 \theta -Fl\sin^2 \theta=0\rightarrow$$...

I know that each material is made up of tiny magnets due to electrons orbiting the nucleus and also from electron spinning about its own axis. In ferromagnetic or paramagnetic rod these tiny magnets align with the applied field causing the net field in the rod to increase. But for diamagnetic...

[FONT=times new roman]Statement : Here is the statement from the text that I paste to the right. Diagram : Does anyone have a diagram (image) as to how does the situation look? Normal Reaction : When a rod rests against a smooth wall, we know that the direction of the reaction is normal to the...

I am having problems understanding point (b) so I would like to know if my reasoning in that part is correct and/or how to think about that part because I don't see how to justify the assumption ##v_y=0\ m/s##. Thanks. I set up the ##xyz## coordinates system in the usual way with ##xy## in the...

I feel like I'm missing something fundamental here. Given only the lengths and the densities, how am I supposed to find a numerical centre of mass?Thought process so far: Are we supposed to use the ratio of the densities to find this answer? like ##\frac{8g/cm^3}{2.7g/cm^3}##? and then use that...

Well, the problem is that, someone told me that a ball won't roll when sliding down a frictionless slope because the resultant force mgsinx is parallel to the slope which means that the ball will slide down the slope. Now, replace the ball with a round headed rod, does this means that the rod...

Hi! A ridged rod is submerged in water at a 45 degree angle toward the bottom of a tank of water. The upper end of the rod is fixed to a pivot point and so, the lower end of the rod is able to move around that pivot point. The lower end of the rod has a float attached to that displaces 50lb...

Summary:: Calculate the deformation on a rod/axle/pipe due to a distributed load. I’m manually trying to calculate the deformation on a rod/axle/pipe due to a distributed load. The rod has an outer diameter of 62mm and an inner diameter of 50, is 170mm long, made from a material with an...

I know that if we bring a positively charged rod closer to the electroscope, charges of electroscope are separated and the leaves of the electroscope get away from each other. but what happens if we touch the positively charged rod with our hands and then move the hand and rod away?

Hello I would love to know how a fishing rod mechanism works. How is the wire always taut? I mean I guess it's a spring. Is it possible to get a consent form from someone? I can not understand how the spring works there Thank you

1) Since the rod is uniform, with mass m and length l, it has a linear mass density of ##\lambda=\frac{m}{l}##, so ##I_{rod_O}=\int_{x=r}^{x=r+l}x^2 \lambda dx=\frac{\lambda}{3}[(r+l)^3-r^3]=\frac{\lambda r^3}{3}[(1+\frac{l}{r})^3-1]=\frac{1}{3}mr^2[3+\frac{3l}{r}+\frac{l^2}{r^2}].##...

Hi. Would it be true to say, that a ferrite rod antenna, operating at fairly low frequencies (say 1Mhz) for all intents and purposes, only responds (in terms of voltage output) to the magnetic field part of a "radio wave"? Thanks.

Hi, I´m trying to solve a special relativity problem, and I think I need some help. There are two inertial frames of reference, ##O## and ##O'##, the last one moving with relative velocity ##v## in the ##x## direction. There's a rod with length ##L'## fixed to frame ##O'##, such that front end...

This is the problem I am working on at the moment. The question states that the bar is at rest in this state. At a 60 degree angle to the horizontal and supported by the vertical spring at B. Small oscillations are introduced and I am required to find the equation of motion and the natural...

Hello ,all I'm calculating the force that required to push steel rod up 50 cm into water filled steel tank . pls see picture . If i exclude negligible friction force (which is friction between steel rod and water sealing gaskets ) Total Force = Force to lift 40 kg rod + Fluid Force...

A bullet with mass m, velocity v perfectly elastically, vertically collide with one end of a rod on a slippery plane and the bullet stops moving after the collision. Find the mass of the stick M the bullet stops moving after an elastic collision, so all energy is transformed to the rod. There...

Could I please ask for a help on how to attack this question? A heavy rod AB of length L can be made to balance across a small smooth peg C when a weight of 2W is suspended from A. Alternatively, it can be made to balance across the peg with a weight of 3W suspended from B. If the distance AC...

Please could I ask for help with the following? Two points, A and B on a horizontal ceiling are at a distance of 2a apart. A uniform rod CD of length a and weight W is suspended from A and B by two light strings AC, BD. A particle of weight (2/5)W is attached to the rod at D, and the system...