Circular Definition and 999 Threads

Homework Statement A ferris wheel with radius 14.0m is turning about a horizontal axis through its center. The linear speed of a passenger on the rim is constand and equal to 7.69m/s. What is the magnitude of the passenger's acceleration as she passes through the lowest point in her circular...

Homework Statement The carnival ride shown in Figure 7-18 has a 2.0 m radius and rotates once each .90 s a. Find the speed of the rider. b. Find the centripetal acceleration of the rider. c. What produces this acceleration? SOLUTIONS PROVIDED: a. 141 b. 98 c. --Explain-- Homework Equations...

Hello, If the position of a particle w.r.t time is given as X=Acos(t)exp(-at), and Y=Asin(t)exp(-at), then it is pretty clear that the particle is moving in concentric circles around the origin with decreasing radius. Is anything else ought to be stated in order to describe the motion of the...

Homework Statement One of the first cyclotrons, built in 1932, has D-s with a diameter of 28 cm, and its magnet was capable of producing magnetic field of 1.4 T. What is the maximal energy of the protons accelerated by this cyclotron? What is the frequency of the circular motion?Homework...

Hi everybody, I'm looking for a way to determine the maximum moment of a uniformly loaded circular plate (diameter = 10") with eccentric circular hole (diameter = 4"). The plate is clamped at outer edge and free at inner edge. The ultimate objectif is to determine the minimum thickness of...

Homework Statement A 990-kg race car can drive around an unbanked turn at a maximum speed of 42 m/s without slipping. The turn has a radius of 140 m. Air flowing over the car's wing exerts a downward-pointing force (called the downforce) of 12000 N on the car. (a) What is the coefficient of...

Homework Statement A car starts from rest and accelerates around a flat curve of radius R = 31.7 m. The tangential component of the car’s acceleration remains constant at at = 2.97 m/s2, while the centripetal acceleration increases to keep the car on the curve as long as possible. The...

Homework Statement For a conical pendulum: Construct a free-body diagram for the pendulum and derive an expression for the acceleration in terms of the gravitational field strength g, the length L of the pendulum, the radius r of the circular path of the pendulum, and the frequency f of...

Hello, This limit \lim_{x \to 0} \frac{ \sin x}{x} is often cited as being an example where L'Hopital's rule cannot be used, since to use it you'd need to differentiate sine; but the derivative of sine, using the limit definition of a derivative, requires that you use the sinx/x limit...

Max. speed you can drive on a circular hill an still be in "Uniform Circular Motion" Homework Statement The top of a hill is in the shape of a circle of radius 25 meters. Homework Equations a) What is the normal force that the road exerts on an 1800kg car as it tops the hill with a...

Let be a photon in a circular orbit (r=3M). I want to know the period measured by a stationary observer at this radius. Because we are working with a photon we cannot 'talk' about proper time, that's why I don't understand how can I calculate this. If I had a massive particle I could do...

A small bead of mass m is moving on a smooth circular wire (radius R) under the action of a force F directed towards a point P at a distance R/2 from the centre .What should be the minimum velocity of the bead at the point where it is closest to P so that it may complete the circle. I worked it...

Homework Statement 0.5kg ball swings in a vertical circle at the end of a 1.5m long string. When the ball is at the bottom of the circle the tension in the string is 15 N. What is the speed of the ball at that point? Homework Equations ac=T/m ac=v^2/r The Attempt at a Solution...

Sorry for having my first post be a question, I guess. I'm just confused as to how to do this since I've never really been one for word problems. I can't really type in... tex(?) either. Oh well, here we go: Homework Statement In an old-fashioned amusement park ride, passengers stand inside...

Homework Statement Imagine that NASA plans to builds a large donut-shaped space station. The station will rotate in outer space in order to simulate gravity. If the station has a radius of 200m, what must be its rotation speed in revolutions per minute, to produce an artificial gravity of 0.8...

Given two particles A and B realizing circular motion respectively on circles with same center o and of radii RA and RB where RA<RB. There angular velocities wA and wB are constant and initially the two objects form an angle θ. How long should the object A waits before he crosses object B...

Homework Statement A circular ring of wire of radius r0 lies in a plane perpendicular to the x-axis and is centered at the origin. The ring has a positive electric charge spread uniformly over it. The electric field in the x-axis direction, E, at the point given by E=kx/((x^2 +r0^2)^(3/2))...

Homework Statement A car is traveling eastward turns north by traveling in a circular path at uniform speed as shown in the picture. the length of arc ABC is 235m and the car completes the turn in 36.0s a) Find the acceleration vector of the car when it is at B. Express answer in terms of...

Homework Statement A 1.01 kg mass is attached to a spring of force constant 9.5 N/cm and placed on a frictionless surface. By how much will the spring stretch if the mass moves along a circular path of radius 0.485 m at a rate of 2.14 revolutions per second? What i was thinking was using the...

A particle of mass 0.014 kg is traveling on a radius 0.9m at a rotational velocity of 36+5*t rad.s-1. How many revolutions does the particle go thorugh in 4.8 seconds? [revs] What is the radial force on the particle at 4.8 seconds? [N] (Hint: consider directions) (question I'm stuck...

Calculating Work Done by Friction in a Circular Track (Answered) Homework Statement A small block with mass 0.0425kg slides in a vertical circle of radius 0.400m on the inside of a circular track. During one of the revolutions of the block, when the block is at the bottom of its path, the...

I would like to compute $$ \iint \limits_{x^2 + y^2 \le 3} \! x^2 + y^2 \, \mathrm{d} A $$ using rectangular coord's. First, I'll compute the iterated integral using polar coordinates so that I can check my work. Limits: $$ 0 \le \theta \le 2\pi \\ 0 \le r \le 3 $$ so $$ \iint \limits_{x^2 +...

Homework Statement Let a body with a mass m move along a circle of radius R. The absolute value (magnitude) of its velocity changes linearly in time from v to 2v during one complete rotation. Find the absolute value of the force that act on this body as a function of time. The Attempt at a...

A wheel of 0.50 m radius rotates at 15 rev/s. What is the acceleration at its outer rim in m/s2 They want tangential acceleration right? Is there anyway to solve this without angular velocity/speed as we haven't learned that yet. This is part of the practice questions for my midterm on...

Homework Statement Scientists want to place a 4400.0 kg satellite in orbit around Mars. They plan to have the satellite orbit at a speed of 2645.0 m/s in a perfectly circular orbit. Here is some information that may help solve this problem: mmars = 6.4191 x 1023 kg rmars = 3.397 x 106 m...

I am very confused with a particular aspect of part of my physics curriculum. Let's say there is an object swinging on a rope swinging in a circular motion. The mass of the object, length of rope, and angle of rope relative to y-axis are known. How does one derive the tension of the rope...

Homework Statement In what direction (using cylindrical coordinates) around a uniformly disk does the electric field NOT point? Homework Equations The directions could be r, θ, or z. The Attempt at a Solution I don't think it can point in the θ or the z direction-- either one would...

I have attempted each problem, but am getting lost on just what to do to solve. If i could be pointed in the right direction on how i should go about each problem that would be nice. Attached are my attempts at problems 1-3. Homework Statement SEE ATTACHMENT The Attempt at a Solution See...

I recently had a problem set with two questions that seemed to give very similar answers. I'm not asking how to do this, so I don't think this post belongs in the homework section. Rather, I'm asking if the similarity I think I see has any deeper meaning in the physics of electric fields...

Hello, I have a couple of questions regarding the calculation of circular orbits in the Schwarzschild exterior spacetime and then the extension of these arguments to other (interior) metrics. First of all, in a few different books/sets of notes there seems to be a bit of 'drift' in the...

Homework Statement A car moves along a straight, but hilly road, at a constant speed. There is a crest and dip in this road, both with a radius of 250m. a) As the car passes over the peak of the crest, the normal force is half the 16kN weight of the car. What is the normal force at the bottom...

Homework Statement A car is moving at a speed of 20 m/s in 4 seconds and the car's tire is 38cm which is its diameter. How many revolutions did your tires make? Homework Equations Relevant Equations, T=2∏r / v The Attempt at a Solution My attempt at a solution: To get...

Homework Statement A roller coaster at an amusement park has a dip that bottoms out in a vertical circle of radius r. A passenger feels the seat of the car pushing upward on her with a force equal to 3.0 times her weight as she goes through the dip.If r=25m, how fast is the roller coaster...

A car is moving at a speed of 20 m/s in 4 seconds and the car's tire is 38cm around which is its diameter. How many revolutions did your tires make? Relevant Equations, T=2∏r / v My attempt at a solution: To get the distance travelled=20 m/s (4 sec.) = 80 m 2∏(0.19m)= 1.19 m 80m /...

The question is: A ball of a mass 4kg is attached to the end of a 1.2m long string and whirled around in a circle that describes a vertical plane..what is the minimum speed that the ball can be moving at and still maintain a circular path? i try solve it by use T+mg=mv*2/r.But i can't find...

Homework Statement There is a block suspended by a string with length 6m forming the radius of a circle. The block is 220kg and you are able to exert a 420N force in the x direction. How far from the vertical will the block travel. m=220kg r=6m F(x)=420 Find x(distance) Homework...

I have a question that I can't quite categorize, which is why I'm putting it in the General Math section, and even the question title doesn't do a very good job of describing it. So here goes: We have a game involving a group of N people seated in a circle. Each person has their own "magic...

Hi.. Speedo, flying in space, is at large speed compared to c relative to his brother on earth. Therefore, after a long time meeting at rest relative to each other, Speedo aged less than did his brother from his brother perspective. But from Speedo's point of view, his brother was also moving...

Hi everyone, I'm new to this forum and I'm having some problem with the question below. Homework Statement A circular track is banked so that a motor cyclist who travels at 40 km/h in a horizontal circle of radius 100 m experiences no tendency to side-slip. If the coefficient of...

Homework Statement A roadway is designed for traffic moving at a speed of 28 m s . A curved section of the roadway is a circular arc of 190 m radius. The roadway is banked so that a vehicle can go around the curve with the lateral friction forces equal to zero Homework Equations F_C =...

Homework Statement I do not know if this is the correct forum to post this in but here goes. I got all of the answers correct, but I just have a question on part F. 1.) The figure shows a motion diagram of a particle in circular motion at a constant speed. The axes have units of...

Circular momentum - Tension of a string. Homework Statement A body of mass 1kg is tied to a string and rotates on a horizontal frictionless table. If the length of the string is 40.0 cm and the speed of revolution is 2m/s, find the tension in the string. 2. The attempt at a solution...

Homework Statement A loop-the-loop machine has radius 18m. What is the minimum speed at which a cart must travel so that it will safely loop the loop? Homework Equations centripetal acceleration: v^2/r velocity=(2r*pi)/t Perhaps more? The Attempt at a Solution To be honest...

1. ______ stands on the Earth's equator. Calculate his tangential speed. The Earth has a radius of 6.38 x 10^6 m. What is ______ centripetal acceleration? 2. 2∏r/T (Circumference/Time) and V2(squared)/r. (Velocity Squared/Radius) I don't even know how to start this problem.

Homework Statement What is the period of Earth's (nearly) circular motion around the Sun? (2*pi*r)/T 1 year (1 year)/(2*pi) (2*pi)/(1 year) 2*pi*(1 year) Homework Equations There is only one speed that a satellite can have if the satellite is to remain in...

Homework Statement An Ferris Wheel has a radius of 16m and rotates once every 20 seconds. a) Find Centripedal acceleration. b) Whats the effektive wheight of a 45 kg person at highest point? c) Lowest point? Homework Equations a) I tried using the a=ω2*r in a) but not sure if its right b)...

Hi I am a little confused regarding circular polarization. I have attached a figure in order to explain the situation I have been thinking of: It shows (to the left) how a magnetic field changes from being positive to being negative. The arrow indicates my quantization axis. To the right I...

Homework Statement A collar of mass m slides without friction along a circular track of radius R as shown in THE ATTACHMENT. Attached to the collar is a linear spring with spring constant K and unstretched length zero. The spring is attached at the fixed point A located a distance 2R from...

Hi ! Does \vec{H}=\frac{1}{\eta}\hat{k}\times \vec{E} always suit an electromagnetic wave ? Because I'm getting some inconsistency for a circular wave :confused: For instance: \vec{E}=E_0(\hat{e}_x+e^{j\frac{\pi}{2}}\hat{e}_y)e^{-jkz} (propagating \hat{e}_z)...