Axis Definition and 928 Threads

(i)Show that the magnetic field \mathbf{B} on the axis of a circular current loop of radius a is \mathbf{B}=\frac{\mu_0 I a^2}{2(a^2+z^2)^{\frac{3}{2}}} \mathbf{\hat{z}} where I is the current and z is the distance along the x-axis from the centre of the loop. I've done this part...

Homework Statement A rigid body is made of three identical thin rods, each with length L=0.600m, fastened together in the form of a letter H. The body is free to rotate about a horizontal axis that runs along the length of one of the legs of the H. The body is allowed to fall from rest from...

ineed your help please ihave two stepper motors and iwant to used in two axis solar tracker but ihaving aproblem in the light sensor icant decided yet the pest kind of sensor,and there are need to use aposition sensor also in my plant.

Homework Statement Imagine a cylinder of radius R and Length L. Both of it's ends are open and it carries a uniform surface charge desnity of sigma (@) Find the electric potential at any point along the axis of the cylinder, and then use that to calculate the electric field at any point...

Homework Statement I have attached a figure showing beam bending around 2 axis. I need to calculate section modulus Sx and Sy but seem to be getting the major and minor axis confused. I guess the problem comes in when I go to select which term is squared in my equation below. Homework...

Homework Statement a) If Vx = 18.00 units and Vy = -15.50 units, determine the magnitude of V. b) Determine the angle of V with respect to the x-axis. Homework Equations The Attempt at a Solution Yeah, Part B is pretty much the only one I don't get . a) Answer is 23.75 b)...

Hello i need help to get this working if its possible, will try explain what i have come to. I have 2 dc motors that I want to control six different axes, if motor 1 spins right and motor 2 spins left then the first axle will rotate. if motor 1 spins left and motor 2 spins right then the...

Homework Statement A cylindrical rod 24.0 cm long with a mass of 1.20 kg and a radius of 1.50 cm has a ball with a diameter of 8.00 cm and a mass of 2.00 kg attached to one end. The arrangement is originally vertical and stationary, with the ball at the top. The apparatus is free to pivot...

Hello folks, I was wondering how to set up a volume of the solid of revolution about a line in the form of a line equation. if i wanted to find the volume about a line of x/4 would I simply find it as v=pi*integral (f(x/4)^2)dx or is there a method I'm missing all togeather?

I have a point p(xp,yp,zp) inside an ellipsoid and i want to find the angle of that point from the center of the ellipsoid(xc,yc,zc) . I also have the major axis length 'a' ,with length ax,ay and az components I calculated the unit vector of axis a with formula length of axis...

Homework Statement I have a point p(xp,yp,zp) inside an ellipsoid and i want to find the angle of that point from the center of the ellipsoid(xc,yc,zc) . I also have the major axis length 'a' ,with length ax,ay and az components I calculated the unit vector of axis a with formula...

The Problem A projectile is thrown from a sloping hill with an initial speed of 20m/s directed perpendicular from the slope. If the incline of the slope is 32 degrees, how far from where it is thrown will the ball land? I found these equations will result in a solution... Want: R = square...

If a two dimensional object (say a circle) spins, their is a zero dimensional 'point' that stays in the same place as it spins. If a three dimensional object (sphere?) spins on its axis, there is a one dimensional 'line' (its axis) such that any part of that sphere that lies on that line...

Is the parallel axis theorem always valid for inertia tensors? We have only seen examples with flat (2d) objects and was wondering if it would also be valid for 3d objects, like a h emisphere, for example. Thanks.

Homework Statement I'm having difficluty in finding the second moment of area and neutral axis of this beam can anyone help Homework Equations The Attempt at a Solution I know that you have to divide the beam into two rectangles, I have used the formula bd3/12 and Izz, i did Izz...

The problem is very similar to #9.74, here: http://books.google.com/books?id=o4-5K8xqlY0C&pg=PA504&lpg=PA504&dq=product+of+inertia+L5+angle&source=web&ots=KMDPgSTiT9&sig=rYBjTLwd-bTiA-IrMRCXB5XNycs&hl=en&sa=X&oi=book_result&resnum=1&ct=result#PPA504,M1" I understand how the parallel axis...

Homework Statement Two particles, each with mass m=0.0036kg, are fastened to each other and to a rotation axis at P, by two thin rods, each with length L=0.68m and each with a mass of 0.0086kg. The combination rotates around the rotation axis with an angular velocity of 13.0rad/s. Find the...

Homework Statement A cone of mass M has a height h and a base diameter R. Find its moment of inertia about its axis of symmetry Homework Equations I=\int R^{2}dmThe Attempt at a Solution I tried starting by finding dm. It's equal to the mass per unit volume, \frac{M}{\frac{1}{3}\pi R^{2}h}...

Hi every body I have a bounce marks on a quistion that i know nothing about its about the Ellipse the Qustion is Find the standerd formula of the eelips which has foci on ( 1,1) and ( -1,-1) and it has a major axis with 4 units. i found that the center in at the origin...

curve ball problem, the spin axis will change?image updated! HI, I encountered a problem about the curve ball (table tennis ball) flying in the air. See the pictures below. A ball with an initial velocity V along X axis, and has a spin along Z axis. As far As I know ( see my previous...

The air drag and magnus pass through spin axis? A ball is flying in the air, and it has spin on y axis, show below. F1 is the air drag force. F2 is the magnus force. My question is: the air drag and the magnus force is pass through the spin axis? Or, the ball will change the torque...

Hello, can anyone explain to me what the moment of inertia is? we learned the mass moment, second moment and the first, and I'm getting confused as to what they all are. and can anyone explain what the strong/weak axis is? is it resistance to bending or rotation? i just can't visualize where the...

y = |x| can't go below the y-axis because a Modulus is always positive, but can you get a modulus that stops x going negitive? Could this be used for things like radioactive decay where the graph should go in -x but doesn't because you can't have - time?

1. I am considering the problem of getting the equation for a 3d vector(magnitude irrelevant) in cartesian coordinates when given 2 angles with respect to arbitrary axes. 2. I think that 180-angle1-angle2=angle3 3. So if the angle between the x-axis and the vector is 60deg, and the angle...

How are torques computed about an axis when the axis (and the attached body) are both accelerating at the same rate? For example, if a car is in free fall with the doors open (with the rear end of the car pointing towards the ground) will the doors shut themselves due to torque? Or, is the...

the solid lies between planes perpendicular to the x-axis at x=1 and x=-1 the cross-sections perpendicular to the x-axis are A) circles whose diameters stretch from the curve y = -1/squrt(1+x^2) to the curve y = 1/squrt(1+x^2) B)vertical squares whose base edges run from the curve y =...

Homework Statement Find the angle between the x-axis and the force F2, and the magnitude of the resultant force? Homework Equations The equation of the triangle: a(squared) = b(squared) + c(squared) - 2bc cos A The Attempt at a Solution What I did was that I said that since the...

If I stretch an ellipse with .5 eccentricity along an axis 45 degrees from its major axis, doubling its area. How do I find the angle of the major axis of the resulting ellipse? Is there a simple rule based on the amount you stretch and the angle and orig eccentricity? Thanks.

Homework Statement A long, 1 kg uniform rod and 1.4 m length, is supported at the left end by a horizontal axis into the page and perpendicular to the rod. The right end is connected to the ceiling by a thin vertical thread so that the rod is horizontal. The thread is burned by a match...

Consider the line L(t)=<4t-1,2+2t>. Then L intersects: 1. the x-axis at point ____ when t=____ 2. the y-axis at point ____ when t=____ 3. the parabola y=x^2 at the points _____ and _____ when t=_____ and t=______ I am confused on how to approach this problem. Do I just make x=4t-1 and y=2+2t?

In coordinate geometry does x=o mean the y-axis or the yz plane!? ? ?

Homework Statement http://65.98.41.146/~grindc/SCREEN01.JPG Find the volume of the solid generated by evolving the region bounded by y = sqrt(x), y = 0, x = 4, when revolved around the line x = 6 Homework Equations The Disk/Washer Method - The Attempt at a Solution let R(y) =...

Hi all. i am integrating in MATLAB and plotting the results in a y-verically and t-horizontally. Matlab automatically plots y versus the time step which is great. but what i need to do is re-label the t-axis so the actual time appears instead of the time step- so instead of from 0 to 1200, it...

Homework Statement Find the volume of the solid obtained by rotating the region under the graph of y=1/x and y=1/x^2 about the vertical axis x=-1 Also given are points on the y-axis (0,2) and (0,5). I guessing these points are specific sections of the graphs where we find the volume...

Homework Statement Actually this is not a homework or course question, but I think it’s quite simple. So maybe it’s suited to post it here. I’m designing a machine that rotates a big object round its own axis. The object has a diameter of 2,7 meter and needs a torque of a least 105Nm to...

Homework Statement A = (1,1,-2) C = (0,1,-5) (in cartesian coordinates) Let A and C be drawn from a common origin and let C rotate about A with an angular velocity of 2 rad/s. Find the velocity of the head of C. Homework Equations v = w x r The Attempt at a Solution w = 2...

if i know a meter is observed at an altitude of 6km, to be traveling with an initial velocity of 20 km/s and the decelerating at a rate dv/dt=0.2km/s^2, which formula i should use to get the length of the semimajor axis of the meteor'orbit?

Homework Statement Find the angle between radius vector of the point M(6,2,9) and: a)x axis ; b)y axis ; c)z axis Homework Equations cos(\vec{a},\vec{b})=\frac{\vec{a} \vec{b}}{|\vec{a}||\vec{b}|} The Attempt at a Solution I tired with...

1. Ok here is a diagram I am HAVE NO IDEA HOW THE 30 DEGREES between the W force came and the radial axis! CAN sOMEONE SHOW ME or EXPLAIN PLZZz I suck at angles! http://img171.imageshack.us/img171/9158/50446152db6.jpg [/URL] W is acting DOWN

Hi, I need help or any sudgestions with the next scenario - I'm designing a sensor for a wind wave tunnel - can be found in the google search using the key words 'wind wave flume' The sensor should give me the speed and frequency of the cappilary gravity waves created in the tunnel by a...

Homework Statement A wheel of diameter of .68m roll without slipping. A point at the top of the wheel moves witha tangential speed of 5.4m/s. Whaat speed is the axle of the wheel moving? What is the angular speed of the wheel? How would i approach to do this problem, what equations would...

A wheel of diameter of .68m roll without slipping. A point at the top of the wheel moves witha tangential speed of 5.4m/s. Whaat speed is the axle of the wheel moving? What is the angular speed of the wheel? Can someone work this problem out, so i can see how its done. My teacher flies...

I remember an analogy with a child's spinning top, that does not rotate in a fixed axis but the axis makes a precessional movement. But the spinning top is sitting on something, it's getting a force from below that's not aligned with its weight, so this force has a torque, etc etc (can't...

Homework Statement Imagine a woman standing on a rotating disc (D) with a rotating wheel in her stretched arms (se picture here: http://image.vandrermodlyset.net/rotation.jpg ). The wheel is oriented in a horizontal plane, with the rotating axis (W) of the wheel parallel to that of the...

Im having a hard time getting my head around this, any help would be much appreciated. Homework Statement Determine the position of the centroid and calculate the second moment of area about a horizontal axis passing through the centroid for the following sections shown. Attached is the...

Homework Statement c) For such a "symmetric" object, prove that any axis going through the center of mass is a principal axis. Homework Equations The Attempt at a Solution I am not sure how they want me to prove this. I was looking at the Displacement Axis Thm but I am not sure...

Homework Statement What are the x and y components of a vector a in the xy plane if its direction is 230° counterclockwise from the positive direction of the x-axis and its magnitude is 2 m? Homework Equations The Attempt at a Solution My main issue is I'm not sure where...

Homework Statement consider the free motion of a plane pendulum whose amplitude is not small. Show that the horizontal component of the motion may be represented by the approximate expression ( components through the 3rd order are included) \ddot{x}+w^{2}_{0} (1+x^{2}_{0}/L^{2})x -...

Homework Statement A cyclist rides around a circular track (R= 30m) such that the point of contact of the wheel on the track moves at a constant speed of 10m/s. The bicycle is banked at 15 degrees inward from the vertical. Find the acceleration of a tack in the tire (.4m radius) as it passed...

Hi there, I'm an electrical engineering student currently building a 2 axis solar tracker. I need to build the frame and I'm posting here because I have no mechanical knowledge at all ... The system is basically two motors, each for each axis which rotates a small solar panel (one rotates...