Angle Definition and 1000 Threads

Homework Statement Calculate the current in the capacitor shown in the figure below if the voltage input is V(t) = 29cos(377t-30) V, C = 1 micro Farad Homework Equations i = C dv/dt The Attempt at a Solution I essentially differntiate V(t) and multiply by 1 * 10^-6. I then get a negative...

Hi this is my first post here. Sorry for this naive question xD I want to calculate antenna gain for which I need the horizontal Φ and vertical θ angle of an antenna beam. The formula for gain is. is it ok to convert the rectangular coordinates of antenna into spherical coordinates and compute...

Homework Statement Given: T(sub-B) plus T(sub-B) prime = 36. Both T(sub-C) values are 0. T (sub-D) =36 and T (sub-D) prime = 12. Find values of T (sub-B) and T (sub-B) prime[/B]Homework Equations OK, so we need to find the wrap angle, which should be 180 + 30 -22, which comes to 188...

Homework Statement Hi everybody, I am trying to do a numerical aplication of change of coordinate system to another; the objective is to calculate the azimut of the sun knowing the altitude, hour angle and declination . Homework Equations Cosh * Sina = Cosδ * Sin H where a is the azimut h is...

Hi everybody, I was messing arround with the program stellarium; I decided to check the hour angle of the sun at 10 am on August 12; it was 19h 53 min; then I did the same for september 4th and it was 20h 0 min. As far as I know it takes 23h 56 minutes to the sun to cross the same point in the...

Can someone explain why the angle inside the triangle inside Mohr's circle is θP2 rather than θP1 ? I understand everything else but just this small point is frustrating me. Thanks

Hi, The reflection coefficient (R) of an EM wave is, as far as I know, 1 if there is total reflection and -1 if there is total reflection AND the phase changes by 180º. However, we also know that the transmission coefficient is given by T = R + 1 (or by its own formula, which should give the...

Homework Statement We consider Rectangle Parallelepiped on a board and a=1m ; b=2m and c=3m. The face a and b is considered touching the board. there’s no sliding; we tilt the board so a is horizontal. Q: Starting from which angle we can see a rotation? Homework Equations I want to know how...

What is the distribution of energy and angle of backscattered electrons from a few MeV heavy ions beam? Someone telled me the energy obeys landau distribution, but I don't know what's the most probable energy.

I need a formula to put an angle between -180 and 180 and recycle if not in the range. I can do it between 0 and 360: angle = deg - 360 * floor(deg / 360) just not between -180 and 180 Oh and what is the name of this function?

Homework Statement The total force needed to drag a box at constant speed across a surface with coefficient of kinetic friction Uk is least when the force is applied at an angle theta such that a.sin(theta) = Uk. b.cos(theta) = Uk. c.tan(theta) = Uk. d.cot(theta) = Uk. e.sec(theta) = Uk...

Hi, This is not really a homework problem, but a project I'm working on. So, I am trying to build a Simulink model for my quadcopter. I derived the equations of motion using the Newtown-Euler method in the body frame to get transnational and angular acceleration. For the transnational part, I...

Homework Statement A point source emits visible light isotropically. Its luminous flux is 0.11 lumen. Find the flux whithin the cone that has half angle of 30 degree from the light source. Homework Equations luminous flux = luminous intensity * solid anlge The Attempt at a Solution I tried...

Homework Statement A rectangular box is being pulled by a rope with a force T on a horizontal surface, with a friction coefficient μ. What is the minimum angle α at which it will lift of the surface? See attached image. Homework Equations \begin{equation*} \tau = rF\sin\alpha \end{equation*}...

Homework Statement Homework Equations p = mv The Attempt at a Solution if an object's velocity at the highest point of a trajectory is 0, how can it still have momentum (since p = mv)? is this question technically correct?

Homework Statement Top-fuel dragsters can accelerate from rest at a rate of about 5g. If this does not sound impressive, consider that for most automobiles the friction between the ground and the tires produces the acceleration. Since the coefficient of friction between regular treaded tires...

Homework Statement The figure below shows the path of a beam of light through several layers (n1 = 1.58, n2 = 1.42, n3 = 1.20 and n4 = 1.00) of different indices of refraction. https://loncapa2.physics.sc.edu/res/brookscole/serway/College_Physics_7ed/Chap22/graphics/serw2244.gif a) If θ1 =...

Homework Statement At the aquarium where you work, a fish has gone missing in a 10.5m -deep, 9.45m -diameter cylindrical tank. You shine a flashlight in from the top edge of the tank, hoping to see if the missing fish is on the bottom. What’s the smallest angle your flashlight beam can make...

I'm trying to figure out how the element of solid angle transforms under a transformation between two inertial frames moving with velocity v w.r.t. each other under an arbitrary direction. But I should say I disappointed myself! Anyway, some books which contain a brief discussion on this(which...

Is there an equation to calculate the oblique shock angle for supersonic flow when the given angle of attack is greater than 0, but less than the half angle? In my particular practical experiment, the half angle of the aerofoil is 5 degrees, so want to get a variety of figures between 5 and -5...

Homework Statement A ramp with an angle given by ø (from the horizon) and a box of mass represented by "m" with a given µ=0.55 between the ramp and the box, find the minimum (critical) ø for which the box will begin to move down the ramp. Wether µ is kinetic or static is not given in the...

Homework Statement Minimal angle of deviation δm of light after passing through prism is connected with index of refraction n and inner angle of prism Φ: If index of refraction and inner angle of prism are directly measured, determine minimal angle of deviation, n=(1.52 ± 0.04) Φ=(30 ±...

Homework Statement Here is my equation that I want to find theta angle Homework EquationsThe Attempt at a Solution I try to set different value of cos (theta) to find theta but it failed , I want to know the main solving strategy Thanks

I've never really understood this bit of trig, I think I get it if there are two parallel angles (parallelogram). But, I do not understand how you go about when the triangles aren't in a parallelogram.

I understand that when light goes between air and water, refraction occurs (either towards or away from the normal). If the light going between air and water is already going in the same direction as the normal, is there no refraction (or a refraction angle of 0 degrees)? Thank you.

Hi there, I have a question I'm unable to get properly started on: A cylinder of radius R and mass m is lodged between cross pieces that make an angle θ with each other, as shown in the diagram below. The cross pieces of negligible mass are connected in point C, with lengths AC = BC = 2R and...

Homework Statement So the full problem is the following: "On the top of a truck, there is a cubic container with a side-lenght of 1,00 m and it's filled with 500 liters of water. The truck accelerates with 2.0 m/s2 in the x-direction during the whole experiment. When the watersurface has...

Homework Statement Sin2x-cosx=1 Solve for all x values between [0,2pi) Homework Equations Sin2x=2sinxcosx The Attempt at a Solution [/B] 2sinxcosx-cosx=1 cosx(2sinx-1)=1 I don't know what to do after this. It doesn't equal 0 so I can't set each factor equal to 0

I kind of understand what to do with this when there are no numbers in front of the expressions, I also kind of understand that you can rewrite 4Sine(4x) as 4Sine(2x+2x) hat do I do with the 4 and 8? In an algebra problem you could divide the 4 into the -8, then simplify that expression, am I...

Hey all, I'm stuck on this problem and not sure how to proceed/if I'm in the right direction. Problem: One reference frame N sits at the origin (inertial frame) while another frame, B, describes a disk rolling on a circular ring about the other frame. Picture below (A) find the direction...

MODERATOR NOTE: THIS THREAD WAS ORIGINALLY IN ANOTHER FORUM, SO THERE IS NO TEMPLATE. I have a hollow shaft made of a titanium alloy, Shear Modulus "G". The shaft has a wall thickness of 3.2mm and an inner diameter of 20mm. The shaft looks as show in the attached image. A torque T of 232 Nmm...

I am trying to design a material transfer system ( the system at duration 0:57 to 1:34 ). The general layout is http://i.imgur.com/ajQ05qy.png It was suggested that angle be 5 degree. The reason is for hauling effect so the tray can revolve back. can you explain this? why 5 degrees? supporting...

I don't need the solution solved for me, but I need help with the method to find the solution. 1. Homework Statement A projectile is launched from an unknown angle and expected to hit a target at a lower altitude. The values given are the initial velocity, and the distance of the target from...

Question: The height of the given vessel is h,and the width of the given vessel is b (as given in the diagram). The density of the liquid is r.Find the force exerted by the liquid on the slant wall. Relevant formulae : P = F/A F = Vdg An attempt at the solution...

Assume a 2D problem. Given a linear antenna array, let's say 3 antennas distributed around the z axis, how could we extract the incidence angle of the received wave? Having 3 antennas equally spaced by λ/2 in the z axis and connected to each other, the result gain would be a function of ϑ (angle...

Homework Statement Find the angle made by the two tangents to the curve ##x=\sin2t## and ##y=\sin(2t)\cos(2t)## at the point ##(0,0)## Homework Equations ##\frac{dy}{dx} = \frac{\frac{dy}{dt}}{\frac{dx}{dt}}## (Derivative of a parametric equation) The Attempt at a Solution ## x = \sin(2t) = 0...

Hi all, I was wondering if anyone could help me with calculating the angle of lean on a motorbike on a banked curve (with friction). If possible proofs would be very useful. Thanks Lee

I ran across a project at the Univ. of Tennessee that has deployed a network of frequency meters around the power grid in the US. see http://fnetpublic.utk.edu/anglecontour.html I understand the frequency excursions may indicate unexpected events like generator trips or loss of load. What do...

Homework Statement A person is dragging a packing crate of mass 100 kg across a rough floor where the coefficient of kinetic friction is 0.400. He exerts a force F just sufficient to keep the crate moving at a constant velocity. At what angle above the horizontal should his pulling force F be...

This was a homework problem; after five tries, I still did not get it, and I can't figure out how to get at the answer the assignment gave me. I could not find the answer anywhere that didn't get into angular velocity, which we are not at yet (and also did not give me the answer!). 1. Problem...

Hi all. I am not quite sure if this is the right forum to place this question but for me there are several forums that would fit with my situation :D I am making a game where I have to throw/shoot a projectile through a 3 dimensional space which has to land on a specific object. There are...

I'm given an irregular shaped plot with 3 sides, and have been asked to find the fourth missing side, no other detail is given. Is it possible to find the missing side? If so, then how? Here is what it looks like roughly:

1. Two forces, 80N and 100N, acting at an angle of 60deg with each other, pull on an object. a) what single force would replace the two forces? r^2=(x^2 + y^2)^2 , sinΘ, cosΘThe Attempt at a Solution I actually got the correct answer by using an angle of 0 degrees for 80N and 60 degrees for...

Homework Statement A train slows down as it rounds a sharp horizontal turn, slowing from 90 km/h to 50 km/h in the 15 s that it takes to round the bend. The radius of the curve is 150 m. Compute the total acceleration at the moment the train speed reaches 50 km/h Homework Equations a =...

If a rapidly rotating gyroscope attached to a perch is released in a horizontal position -- that is, so that the axis of the gyroscope is horizontal -- the gyroscope will precess around it's perch. Let L represent its angular momentum. Let dL represent a small change in that momentum. Let dA...

Homework Statement A bob of mass m is suspended from the ceiling of a train moving with an acceleration g/√3 (a) If an observer is sitting inside the train, what angle with the vertical will he observe? (b) If an observer is standing on the platform, what angle will he observe? Homework...

I said stay the same, the definition of co efficient is here http://simple.wikipedia.org/wiki/Coefficient_of_friction but the main part i saw not only here was "The coefficient of friction is dimensionless, meaning it does not have any units. It is a...

1. Problem Statement: Consider the scattering of an alpha particle from the positively charged part of the Thomson plum-pudding model. Let the kinetic energy of the α particle be K (nonrelativistic) and let the atomic radius be R. (a) Assuming that the maximum transverse Coulomb force acts on...

Homework Statement "Show that particles hitting a plane boundary have traveled a distance 2λ/3 perpendicular to the plane since their last collision, on average."Homework Equations (Root mean path squared) <x> = 2^(.5)λ λ = ( 2^(.5) * n * sigma )^(-1) ANSWER: The Attempt at a Solution...

Homework Statement Assume two stars are in circular orbit around a mutual center of mass and are separated by d = a. Assume angle of inclination is i and stellar radii are r1 and r2. Find an expression for the smallest angle of inclination that will just barely produce an eclipse. Homework...