Circular Definition and 999 Threads

I made notes on this in class, but I did not understand everything about it. So, what I know is that vertical motion is when the object goes around in a circle like this: And horizontal I guess it is like this: But then I am very confused regarding what my teacher told me for horizontal...

Homework Statement Please could someone help explain the case of a friction-less banked race track. If you take an Olympic indoor banked cycle track and imagine for a moment that it was friction-less. The laws of circular motion tell us that without friction the banked geometry can enable a...

Hi Guys, I am trying to understand that how does the frictional force on a car moving in a circle is directed towards the centre? I do understand that kinetic friction acts tangentially to the motion and opposite to the velocity vector but why does static friction act towards...

Homework Statement Your niece finds her father's watch. The light watch chain has a length of 35 cm, and the mass of the watch is 190 g. Your niece swings the watch in a vertical circle, maintaining the speed of the watch at 2.4 m/s. Find the tension in the chain when it makes an angle of 43°...

Homework Statement The problem statement is in the attachments.Homework Equations F=maThe Attempt at a Solution I uploaded the solution to the problem. I have had no trouble deriving the first two equations for the summation of forces in the x, n and t directions, however I am having trouble...

Two parallel electromagnets situated symmetrically on either side of the straight section of an oval track propel a wheeled trolley along the track, so that the trolley is in continuous motion, as long as the current is supplied to the electromagnets. Is this workable? Does the entry and exit...

The question is: If an astronaut who can physically withstand acceleration up to 9 times that of free fall (9g) is being rotated in an arm of length 5.0m what is the maximum number of revolutions per second permissible. I approached this by considering 9g to be the centripetal acceleration...

Homework Statement Could someone please help me with this quesiton 4. The Earth revolves about its axis every 24 hours. Find the magnitude of the average acceleration of a point on the equator over a 5-hour time interval. (The radius of the Earth is 6.38 x 106 m.) Homework...

Homework Statement An object is constrained to move in a circular path of radius r = 3.1 m. At the instant diagrammed in the Figure 1, the directions of the velocity and acceleration are indicated by the v and a, respectively.The magnitude of the acceleration is a = 11.2 m/s^2 and the angle...

Homework Statement I have attached questions about gravitron. I'm struggling with question 2 about calculating the normal force of the gravitron. Homework Equations mv^2/r The Attempt at a Solution I know the answer so I can figure it out as I know it involves setting the...

I'm wondering if someone is observing a situation from a frame moving in a uniform circular motion, would that frame of reference be considered inertial? I'm unsure because of the centripetal acceleration towards the center.

Relativator (Posted Feb10-06 at 10:39 PM by robphy). The Dec 2005/Jan 2006 issue of Fermilab/SLAC's publication http://www.symmetrymag.org/cms/ has a story http://www.symmetrymag.org/cms/?pid=1000234, "A circular slide-rule [which] allowed enthusiasts to perform calculations of Einstein's...

Homework Statement Calculate Mutual-inductance of a circular cross section toroid. circular cross-section radius :a toroid mean radius :R Previous attempt for self inductance :https://www.physicsforums.com/showthread.php?t=537149 Homework Equations B=μNI/(2pi(R+y))...

Currently we're discussing uniform circular motion in my physics class. The previous unit discussed vectors and vector addition in the i, j, k format. When I try to apply the rules for vector addition to find the resultant velocity in uniform circular motion, I get an increase in the...

Hey! I need to calculate the electric field on the axis of a circular plate of radius a with the following charge distribution: \sigma_0 \frac{r^2}{a^2} \delta (z), \; r\leq a0, \; r>a where \sigma_0 is a constant. I've already calculated the potential and taken its gradient to get the...

In uniform circular motion, (eg, a mass on the end of a string moving in a horizontal circle) centripetal force is the only thing causing acceleration. we have the kinematic relationship V=RW or velocity is proportional to radius. I.e a bigger radius means greater linear speed? For the...

A particle of mass m is inside a long, narrow tube which rotates a constant angular velocity ω in the horizontal plane. (This means that you see the tube from the top of the figure and not from the side.) At time t = 0 is the particle on the radial distance a from the rotational axis and the...

How do you find the angle b/w tangential acceleration and total acceleration vector, Or angle between velocity vector and Acceleration vector. I'm really confused about this and no one's helping.

These equations model circular motion. Equation R is the position vector given in polar coordinates. What I've done is represent this vector onto the complex plane via equation (1). Equation (2) and (3) are the first and second time-derivatives, respectively. Now, the question I have is this...

Homework Statement Please see attached image file I understand everything in this problem except I don't know how they got (1/4) in the area of a coil. Can someone explain this? I have googled it and I am not getting a clear answer. I thought the area of a coil could be (pi(r)^2)L...

Definition/Summary This entry describes diffraction of a wave when it passes through a circular aperture. Equations The far-field (Fraunhofer) diffraction pattern for a circular aperture of radius r has a power per area (irradiance) given by: I(\theta) = I(0) \left( \frac{2 J_1(k \ r \...

Hi everyone, I need to calculate the force required for machining a circular tube of outer dia 32 and a wall thickness of 2.3, how much ll be the force required for the machining the outer dia to 25?

Consider a circular loop of radius R that carrys a uniform current I. We know(by Biot-Savart law) that the magnetic field it produces on its axis is given by \vec{B}=\frac{\mu_0 I R^2 \hat z }{2(z^2+R^2)^\frac 3 2} . But let's calculate its vector potential: \vec{A}=\frac{\mu_0}{4\pi} \int...

Homework Statement Acrobat-dude swings two cups of liquid which are attached to ends of a string. He swings the two cups by holding onto the middle of the string. The acrobat then releases his hold on the string and the question asks what is the tension in the string at this point. The...

Homework Statement when a stone is thrown to position O (in a pond), a wave is generated and the wave eventually spread out form the center, my question is will the amplitude of particle of A, B and C change? the wave intensity is I= 0.5m(w^2)(a^2)s^-1/ 2 pi r so i have i got I is...

Homework Statement Find the electric field a distance z above the center of a circular loop of radius r that carries a uniform line charge λ. Homework Equations $$E=E_r\hat{r}+E_z\hat{z}$$ $$E_r=\frac{\lambda}{4\pi\epsilon_0}\int_0^r\frac{1}{\mathcal{R}^2}\sin{\theta}\,dr$$...

why simple harmonic motion is projected as or compared with uniform circular motion ?

Homework Statement hi all, why the wave is reflected back form the centre when it is at the distance of 200mm? why the wave can't go beyond 200mm to reach 250mm from the side of bowl? Homework Equations The Attempt at a Solution

Homework Statement Question 1. If two objects were in the same orbit around a planet they would both have the same orbital velocity regardless of their mass. Using the equation given, explain why an object with twice the mass experiences the same orbital velocity. Homework Equations...

Homework Statement Write an expression for a light wave circular polarized to the right, traveling in the positive ZZ direction, such that the electric field points in the negative XX direction at z=0, t=0.Homework Equations Right handed polarization is the same as clockwise, I think...

Find the radius of the circular section of the sphere of the sphere x^2 + y^2 + z^2 = 49 by the plane 2x+3y-z-5 \sqrt{14}= 0

We know that the magnitude of tangential component of acceleration is, atangential = dv/dt (where v is speed) So clearly atan = 0 for uniform circular motion (as v is constant) But what about non-uniform circular motion? I can see atan = 0 only when v = constant. But in non uniform circular...

Homework Statement So I just sat an exam today and I'm not sure how I did in this question. I think I did bad in it. http://www.examinations.ie/archive/exampapers/2014/LC020GLP000EV.pdf Its question 8Homework Equations F = mv^2/r v=ωr t=2(pi)r/v The Attempt at a Solution Q9 (a)...

Here is the problem I am working on: A steel ball is accelerated around a circular track of radius 72 cm from rest. after 3 circuits the ball reaches a speed of 4.00 m/s, assuming tangential acceleration, a_{T} , is constant, how long after the ball starts moving is radial acceleration, a_r ...

when the body rotates with uniform motion then the normal acceleration is V^2/r. but what is the normal acceleration when the motion is in non uniform circular motion let's say when body has uniform tangential acceleration.

My question is essentially a variation of the Ehrenfest paradox in SR. But hopefully with some experimental data. In the LHC, for example, a fixed number of particle bunches with some length are injected into the main ring. Now, as the velocity of the particles increases, the bunches would be...

Hi everyone, If you have a horizontal circular motion (with gravity action on the object), what holds the object up in the horizontal plane? All vertical components of the tension go to zero when the angle with the vertical axis is 90°... Where am I going wrong? Thanks Ramana

A circular disc of 10 feet radius has to carry load 5 tonnes and it has to rotate very slowly say .. 1 rpm. how much power hp motor should be used? Can Anybody help me with thie.. Man thanks in advance...

A interesting question came up to my mind, and it's related to the concept of different synchonization methods. If we change the synchronization parameter from 1/2 to some other value, light will have different velocities in opposite directions, which implies that two velocities with opposite...

Homework Statement The diagram shows a smooth thin tube through which passes a string with masses m and M attached to its ends. The tube is moved so that the mass m travels in a horizontal circle of radius r at constant speed v http://quickpic.info/z/yb.jpg Find an expression for M...

In introductory physics books (or at least mine) it limits the equation a_c=\frac{v^2}{r} to the sitaution where the speed around the circular path is constant. It enforces the idea that the speed is CONSTANT. But wouldn't the equation also apply to non-constant speeds? (a_c would just...

Hi all, For a marble in uniform circular motion within a smooth cone, what is the relationship between the normal force by the surface of the cone and the weight of the marble? My take is that the normal force forms a reaction pair with one of the resolved forces of weight. I have resolved the...

Q: During an earthquake, a skyscraper is designed to sway back and forth with simple harmonic motion with a period of 8 secs. The amplitude at the top floor of a particular earthquake is 70 cm. With respect to the simple harmonic motion of the top floor, calculate the following quantities: a)...

Homework Statement The minute hand of a clock is 4cm long. Find the average velocity of the tip of the minute hand between 11.00 am to 11.30 am. (in m/s)Homework Equations The Attempt at a Solution 1.In the motion between 11 am to 11.30 am, \theta=180^o=\pi \text{radiaans}\\ radius=4cm\\...

Hi all I'm from Bioengineering and unfortunately not too expert on the mechanical side. I'm making a device for which I need a mechanism to transform circular motion into oscillatory motion. I found the mechanism in the picture below...

Homework Statement In a zero gravity experiment a spring has a rest length of 1.0 metre. It is attached at each end to 1.0 kg masses. The combination is then set rotating about its centre of mass at 1.0 revolution per second. Each mass undergoes uniform circular motion with a radius of 70 cm...

Please look at pictures. I do not understand the solutions; Here is how I find length of string: 5m/s*1.2s/rev=6m/rev=circumference=2piR R=0.95m. For the force: T=mv^2/r= 0.350 kg *5^2/0.95= 9.21N They got 9.16N?

I was just wondering how the kinetic energy in, for example, a car undergoing circular motion is constant. We know that it's constantly acceleration due to the constant change in velocity, but surely that means that in the KE equation (1/2mv^2) the velocity is constantly changing as well. This...

I've been trying to work out the forces on a car in circular motion around a turn and I'm having trouble understanding what causes a friction force to be directed inward toward the center of the circle. I understand that on a straight path, the torque on the wheels causes them to push back...

Homework Statement Acceleration is a vector representing the rate of change of velocity. An object moving in a circle at constant speed: A. accelerates without changing its velocity B. Has constant acceleration C. Changes speed but not velocity D. Changes velocity but not speed...