Angle Definition and 1000 Threads

Homework Statement Two positively charged metal spheres are suspended from the same hook by light strings of equal length, making an angle of 10.0◦ with each other. The charges carried by the spheres are as shown in the diagram. After that, the spheres are brought in contact briefly, then...

1. Homework Statement Hi. This is my first question on PF so please forgive me if something's not right So I'm stuck at this question in EMT In frame1, E and B are parallel and related by E=cB. We are required to find the cosine of the angle between electric field E' and magnetic field B' in...

ok don't know the book answer but think this is ok suggestions welcome:cool: $\tiny{t12.3.11}\\$ $\textsf{Find the angle between vectors}$ \begin{align*}\displaystyle u&=\sqrt{3i}-7j\\ v&=\sqrt{3i}+j-2k\\ u \cdot v&=(\sqrt{3})(\sqrt{3}) + (-7)(1)+(0)(-2)\\ &=3-7+0\\ &=-4 \end{align*}...

Homework Statement Hello, I can find the magnitude of Fnet from free body diagrams or from addition of vectors. My issue however is how do I know when to subtract the angle I found with the corner angle? I've attached two questions and the answers to them. In the first question, the angle...

Homework Statement Hi guys, i came across a paper about an Investigation of pencil-lead breaks as acoustic Emission sources by Markus G.R. Sause (it's downloadable everywhere). The Setup of the Experiment can be seen in the Picture i attached. Now the Problem i have is to find the correct...

I just watched this video that perfectly explains how to derive the equations for the slip angle of a car: However, how could this be done for a three axle system (car-trailer)? Would you have to express distance a (in the video) in terms of b (distance from centre of gravity to the second...

Homework Statement A projectile, launched at A with an initial velovity of 24m/s at the angle θ, impacts the vertical wall at B. Compute the angle θ that will maximize the height of h of the impact point. What is this maximum height? Homework EquationsThe Attempt at a Solution I guess I have...

Homework Statement I want to solve the motion equation ## m \frac {dv_z} {dt} = - μ \frac {∂B_z} {∂z} ## with small angle approximation Homework Equations ## B_z(z) = B_0 -bCos(\frac {zπ} {2L}) ## is the magnetic field in the z-direction The Attempt at a Solution Started by derive the...

I find this question rather difficult! Q1. I take Fig 1-11 to be the laboratory frame and ##v## to be the velocity of the ether wind. Since Lorentz length contraction occurs only horizontally, the right mirror should be further to the right horizontally in the ether frame. This makes the angle...

Find cos(z) and sin(z) if z is an angle in quadrant III (in standard position) and the terminal side of angle z is parallel to the line 3x+4y=12. I just want to make sure I'm thinking about this correctly: The definition of an angle in standard position is that the vertex is at (0,0) and the...

In triangle ABC point $N \in BC$ , point $P \in AN$. Let $\angle ANB = 90$° $\angle PBA = 20$° $\angle PBC = 40$° $\angle PCB = 30$°. Find $\angle PCA$. I don't know how to solve that. Maby it was.

Homework Statement A 3.0 kg block is released from the top of a rough ramp of length 2.0m and accelerates down the ramp at 1.6m/s^2. If a force of kinetic friction of 10 N acts on the block, what is the angle of the ramp. Homework Equations Fnet=ma ff=(mu? I don't have that symbol HAHA) muFn...

A certain planet has a vector (Recl, L, B). The Earth and Sun vector exists on ecliptic. I need to know how to calculate the compound angle between the planet vector and the Earth-Sun vector.

From the Wikipedia article https://en.wikipedia.org/wiki/Small-angle_approximation, it says that they are "second-order approximations." What makes all three second order? Shouldn't sin and tan be first-order and cos be second-order?

Hey! :o We have the triangle ABC with $c=18$, $\alpha=\frac{\pi}{6}$ and the median through $C$ has the length $5$. I want to determine all the possibilities for $a$ and $\gamma$. I have done the following: From the median we have the following...

Homework Statement Homework EquationsThe Attempt at a Solution A) [/B] s = √[(x2) + (y2 ) ]= a√[2(1- cos (ωt) ) ]|t= Γ The book says, s = aωΓ What I can do is , For very small Γ i.e. ωΓ<<1 , cos (ωΓ) ≈ 1 - {(ωΓ)2}/2 Then , I get, s = aωΓBut, in question it is not given that ωΓ<<1. So...

Homework Statement A plate is subjected to rays from a light source located 35 degrees above the horizon. The plate itself is tilted 12.5 degrees around its vertical axis reducing the exposure to the light source. Find the incidence angle between the light source and the front face of the...

I googled a lot on proof of Gauss theorem and nearly every other proof (on web and so on books) state that solid angle of closed surface is 4pi but I can't find the proof of this nowhere ! I tried setting up the integral but don't know how to proceed furthur : Ω=∫(cosθ/r^2)*dA Also The one...

Hello Everybody! Concept of Solid Angle was pretty much straight forward until they were on surface patches were taken into account which were visualized as base of cone. I am having difficult when 3d Objects like Sphere/Cylinder . We can very easily calculate the respective area and plugin the...

Homework Statement Homework Equations Equation given in question. The Attempt at a Solution The only thing I could think of was to try changing the y=3x^3 into polar coordinates but I didn't know where to go from there... Could I get some direction to how I should go about this, I'm sort of...

Hi all, According to the sunrise equation, the hour angle of the sun at sunset is: cos H = -tan(a)tan(d) where H = the hour angle, a = latitude and d = solar declination angle. This equation says that H at sunset = -H at sunrise. Now, I have a few questions concerning that: 1) I was...

hi all, Just a quick question, what would the load angle be of a synchronous motor when running at no load. would it be 0 degrees or 45 degrees

Homework Statement : [/B] r vector = 3t i + (4t-5t2)j. Find the angle made by the vector with respect to the x-axis and the y-axis. 2. Homework Equations : A.B=AxBx+AyBy 3. The Attempt at a Solution : I tried to take the dot product of the unit vector along x-axis and r. I did the same...

Homework Statement Homework Equations Snell's Law sin tetha1/v1 = sin tetha2/v2 n1 = c/v1 n1 . sin tetha 1 = n2 . sin tetha 2 The Attempt at a Solution I try to make triangle out of line PO, so that it will have correlation to tetha, since o = center, then let's say there's point C at...

Hello, A friend of mine challenged me with a question related to erection of missile launcher. For some reason and after too long struggling with it i gave up and trying now to figure out what is the point that I'm missing. The task is to fine the force that the piston is "feeling" as function...

Homework Statement [/B] imgur.com/a/bsAKl [I didn't know how else to upload an image from my iPad] In this problem: -Center of the circle=Point F -Arc AB= 110 degrees -Arc CD= 40 degrees Find the measure of angle E. Homework Equations I know of some equations, but I don't know if they...

A little review of trigonometry. A man 1.5m tall is standing 4m away from a pole. If the angle of elevation of the top of the pole is 30 degree, calculate the height of the pole. My set up is here. Let x = height of pole 1.5 + tan30 = x/4 4*tan(30) = x + 4(1.5) Correct?

1. Find α(β) given that the sum of the 2 sides= ##(x+y)## and its third, ##z## is a constant for 0<β<180. You can imagine that there's two pieces of string connected between two points. One string is as long as the distance between the two points while the other string is longer. If you...

Homework Statement A crate is placed on an adjustable, inclined board. The coefficient of static friction between the crate and the board is 0.29. A) Calculate the angle at which the crate just begins to slip. Homework Equations Sum of Forces=M*A The Attempt at a Solution In my problem: Why...

$\triangle ABC ,if \,\, \angle BAC=\angle ACB=50^o$ point $M$ is an inner point of $\triangle ABC ,$ given :$\angle MAC=10^o$ and $\angle MCA=30^o$ find the value of $\angle BMC=?$

Homework Statement I had know that for finding magnetic flux is NBA cos theta. The answer is C though, so why is it sin theta instead of cos theta? I wonder Homework Equations BA cos theta NBA cos theta[/B] The Attempt at a Solution

A pretty straightforward question because right now I can't think how it works: The missing transverse momentum azimuthial angle (φ) is calculated by measuring the x- and y- components of the missing transverse momentum E_x,E_y and taking: \phi^{miss} = arctan(E_y/E_x)...

Homework Statement I guess this is a general question. in the book, it was originally in a normal form, but it was then converted into a double angle form, which I would have to use double angle forumla to compute, so what's the point of simplifying in the first place? Homework EquationsThe...

Hello I would need help to continue. calculation problem: Given a right angled triangle with catheter lengths a and b length units, determine and indicate the length of the bisectris to the right angle. find: Xa^2 + b^2 = (y+z)^2X^2 + y^2 = a ^2X^2 + z^2 = b ^2

Homework Statement A non-transclucent container in the form of a cylinder, has a diameter of 3.00 m, has its top part open, and is filled with water. When the sun created a 28.0 degree angle with the horizontal, the light doesn't illuminate the bottom of the container. What's the depth of the...

Homework Statement Hello! Please, take a look at the exercise I post below. I have solved it correctly, and I understand how to solve it; so no problems here. But what I do have a problem with is the size of the angle between two points. Please, see details below. I will be grateful for your...

Homework Statement Hello! Please, take a look at the following equation and help me to understand where the authors got the value of φ = π/3. I don't see where it is derived from as no additional conditions are given. Homework Equations x(t) = 5e(-t/5) cos(t) + 5e(-t/5) √3 sin(t) The...

Homework Statement So, my physics professor has been behind all semester long and basically taught the entire light wave and optics chapters in a single day and explained absolutely nothing, hence massive confusion on the following problem:[In a double-slit experiment, the slit separation is...

Okay, this might be a tad silly, but I cam across this graph/picture i my physics textbook, and for the life of me I can't figure out how to connect the two angles. Here, have a look: It's not a big part of what the paragraph is about, so in theory I could just skip it, but it's been...

Hi there, i want to know as much as possible about this situation. I want to know the angles of vision for a real image, where can one see the image, the location of our eye to see it. Which factors determine this angle Thank you so much :D I hope this isn't a dumb question, thanks.

Can someone please help me with this question? Any help would be really much appreciated. Thanks all and have a great Easter!

Homework Statement A block lies on an inclined plane with an angle of elevation theta. The inclined plane is frictionless, and the plane is accelerated to the left such that the block's height remains constant. What is the net force on the block? I'm having trouble figuring out how to draw the...

Homework Statement I'm about to conduct an experiment about factors that affect the flight of an elastic band. The aim of this experiment is to find how the angle of launch, when shooting a rubber band, affects the range or distance of the shot. Do you suggest to consider the drag force? like...

If air drag is a factor, how will it affect a projectile’s trajectory qualitatively? Its velocity? Its acceleration?

Homework Statement I'm doing a lab report about how the launch angle affects the range of a projectile. Independent Variable Angle of Launch Dependent Variable Range or distance I did an experiment with three trials and here are my results: And then plotted the data. However, it's a...

Hi, hopefully a quick question here...how do you calculate the angle between two vectors if the only information you have is the value of their scalar product and the magnitude of their cross product? Thanks! Andy

Hello, I have a question about why I can't determine the angle between two vectors using their cross product. Say there are two vectors in the XY-plane that we want to find the angle between: A = -2.00i + 6.00j B = 2.00i - 3.00j The method to do this would be to work out the scalar product of...

Homework Statement A wooden block with mass of .0507 kg is placed at the midpoint of a 1m long wooden board, where the coefficient of kinetic friction (mk) = .275, at what angle should the board be placed so that the block takes time t = .387 s to slide to the lower end of the board? You may...

Background info (Not actual question): So I've been gone a week from university and I've missed a lot of content, one particular thing that boggles me is this new method to operate with vector magnitudes and their angles. The operations surprised me with the speed they were done. I did ask a...

Hi, Calculating the angles in 3D shapes can be a very frustrating and annoying thing. So, I was wondering, are there any mathematical terms, which describe a 3d angles?( "angles" between three lines- part of a sphere) If there are such terms, suppose a triangular pyramid. Is the sum of those...