Angle Definition and 1000 Threads

Homework Statement "Find the tension in the right string, when the left string is cut, if the mass of the rod is ##m## and its length is ##l##, and ##\sin \theta = 3/5##. The rod is initially horizontal." Please refer the diagram below (sorry for its clumsiness!). Homework Equations $$I_{rod}...

Hello! (Wave) A ship that is at the position $(1,0)$ of a chart ( with the north at the positive direction $y$) "sees" a rock at the position $(2,4)$. Which is the vector that connects the ship with the rock? What angle $\theta$ does this vector form with the direction of the north? I have...

Homework Statement Ball strikes inclined plane of infinite mass with velocity v vertically. Elastic collisions. Velocity and direction after collision? One way of solving is take components along and perpendicular to inclined plane and then solve easily. Is there any way to solve is using...

Hey guys, I'm having difficulty with my university project which is to build an electric bike. My design is to have a friction wheel attached to the shaft of my 800W 2800rpm electric motor which is rated at 2.8Nm. I have two issues with my spreadsheets at the moment. Can someone please help...

Could anyone please tell me how to get this answer through calculations and other means?

Hi. I'm a computer science student developing a kalman filter for autonomous sailboat, but I severely lack knowledge of the physics behind sailboats. I have a wind sensor giving data about wind speed and wind velocity, problem is the data is unreliable. So i thought that i could estimate what...

In ultrasound what is the difference between beam steering angle and Doppler angle thanks

I'm curious if it looks like I defined the reasons correctly to prove that FBCD is indeed a parallelogram. Specifically, I'm unsure if I'm using #4 "definition of coincident" and #5,6 "reflexive property" correctly in their terminology. I don't have anyone else, or any teacher to ping this...

Homework Statement You have a device that shoots an object at an angle, on top of a desk. You have x,y and v solve for the angle. Origin is at the top of the desk. Homework Equations y=vyot+(½)ayt2 x = vxot vsinΘ = vyo vcosΘ = vxo The Attempt at a Solution y= vsinΘt + (1/2)at^2 x = vcosΘt →...

Homework Statement Mass ##M## hangs from a string of length ##l## which is attached to a rod rotating at constant angular frequency ##\omega##. The mass moves with a steady speed in a circular path of constant radius. Find ##\alpha##, the angle the string makes with the vertical. Homework...

why light can't penetrate the prism with 45 degree angle?

Homework Statement Charges 2q and -q are located on the x-axis at x=0 and x=a respectively. (a) Find the point on the x-axis where the electric field is zero, and make a rough sketch of some field lines. (b) You should find that some of the field lines that start on the 2q charge end up on...

I'm building a clothing rack that swings out of the way. It's ideally made of 7/8" (or possibly 1") stainless steel tube, with 1/16" thickness and will sit on a 3" bearing (lazy susan) that supports 200lb. The top is firmly attached to a stud in the sloped ceiling. It needs to hold up something...

Here is the problem verbatim: The polar and azimuthal angles of a vector are Θ1 and Φ1. The polar and azimuthal angles of a second vector are Θ2 and Φ2. Show that the angle ϒ between the two vectors satisfies the relation: cos ϒ = cosΘ1*cos Θ2+sinΘ1*sinΘ2*cos(Φ1-Φ2) Hint: write out the...

Homework Statement Homework Equations ## θ_{brewster} = arctan(\frac{n_2}{n_1}) ## The Attempt at a Solution Hi all I'm having difficulty on this part of a question Now, showing that all light passes through is to say that there be no reflection. This occurs when the angle of incidence...

Homework Statement A block of mass m slides down a frictionless ramp from height h above the floor. At the base of the ramp it collides and sticks to the lower end of a uniform rod, length L, mass 2m, that is suspended about a pivot at point O, about which it is free to rotate. Express...

Homework Statement Homework EquationsThe Attempt at a Solution Using parallel lines I got the angle as theta.

Homework Statement Show that vector C = (BA + AB) / (A + B) is an angle bisector of A and B. Where vectors are represented by bold font, and magnitudes are regular font. Homework Equations A ⋅ C = A C cos(θ) ⇒ cos(θ) = (A ⋅ C) / (A C) B ⋅ C = B C cos(θ) ⇒ cos(θ) = (B ⋅ C) / (B C)The...

Homework Statement I have to do a high school report investigating the relationship between the angle of descent and the velocity of a ball rolling across a horizontal surface after it has gone through a ramp. I have collected the data already with the use of photo gates that measured the...

Hello! In this previous post, most replies point out that it is not possible to predict the angle of refraction (and so the frequency) at a certain interface, given the wavelength of the original signal. In particular, But when dealing with optical waveguides, it seems to be different. I am...

Homework Statement If a vector makes 45 degrees and 60 degrees with x-axis and y-axis respectively then the angle it makes with z-axis is equal to Homework EquationsThe Attempt at a Solution

Homework Statement Homework Equations ΣFx=max The Attempt at a Solution I drew a free body diagram for the box and set up the equation to solve for θ, but I'm not sure how to do it without μ

Homework Statement 2 parallel plates of length 4.0 cm are arranged horizontally in a vacuum. The upper plate is positively charged and the lower plate is negatively charged. An electron is projected horizontally with an initial velocity of 6.0 x 106 ms-1 and experiences a constant electric...

I recently came across an equation stating that ## \lambda_{ob} = \frac{\lambda}{cos(\alpha)} ## if ##\alpha## is the angle the observer is relative to the wave's direction of propagation. I guess I can kind of understand that a person perpendicular (i.e. ##\alpha = 1##) would see the normal...

OK I'm about to grow (more) gray hairs... Could some friendly soul smarter than myself kindly help me solve for both f and theta respectively in the following equation, please: x = sin[ (pi*f*W)/c * sin(theta) ] / [ (pi*f*W)/c * sin(theta) ] Getting stuck at "arcsin of arcsin" sort of...

Homework Statement A ski jumper leaves the ski track moving in the horizontal direction with a speed of 25.0 m/s as shown in Figure 4.14. The landing incline below her falls off with a slope of 35.0°. Where does she land on the incline? I've attached an image of the problem, my work is below...

Homework Statement When completing this problem I am able to find a value for the phase angle but am unsure of how to find the quadrant for the phase angle therefore unable to get the correct phase angle. Homework Equations Provided in the question: x = xmcos(wt+ phi) The Attempt at a...

Homework Statement Hi! I need to find the opening angle of the loss cone at a given altitude, when the magnetic latitude is 65 deg. Homework Equations See below The Attempt at a Solution First, I used the following equation to calculate the magnetic field at a given altitude...

Homework Statement You have a geostationary satellite (location 0◦N 0◦E, 36000 km above geoid). Assume the Earth to be spherical with a radius of REarth = 6372km When observing a region centered at 60◦N 0◦E: What is the incidence angle of the satellite’s line of sight (at pixel center...

Circulation of a magnetic field = closed loop integral ∫c B ⋅dl = μ0I B is mag field strength, dl is small line element, I is current Im imagining both B and dl point in the same direction from the diagram. So the dot product here, I picture as cosθ = cos0 Is that correct way to...

Homework Statement At midnight (local time) on Dec 21st 2015, the Local Sidereal Time at Palomar Observatory, California, was 6h 27m. Palomar Observatory has latitude 33◦ 210 2100 N, and longitude 116deg 51arcmin 60arcsecW. a) What was the approximate Local Hour Angle of the Sun at 23:00 local...

Homework Statement Four identical balls are thrown from the top of a cliff, each with the same speed. The first is thrown straight up, the second is thrown at 30° above the horizontal, the third at 30° below he horizontal, and the fourth straight down. How do the speeds and kinetic energies of...

If I have an electric field between a cathode and an anode, are there electric field lines between the plates? If yes, what happens if a charged particle enters the field at an angle? Is the force acting on the particle reduced?

Homework Statement Given two waves characterized by y1(t) = 3 cos wt; y2(t) = 3 sin(wt + 60deg); does y2(t) lead or lag y1(t) and by what phase angle? Homework Equations y1(t) = 3 cos wt; y2(t) = 3 sin(wt + 60deg) The formula I'm given in my book Fundamentals of Applied Electromagnetics is...

Homework Statement Canada geese migrate essentially along a north-south direction for well over a thousand kilometers in some cases, traveling at speeds up to about 100 km/h. The one goose is flying at 100 km/h relative to the air but a 38 km/h -km/h wind is blowing from west to east. At what...

Hello everyone, I am trying to figure out how to explain an aspect of this question to my students, but cannot seem to recall the geometry that explains the textbook's approach. In the figure below, for part (b) of the question, we are using the angles of refraction at the left boundary to...

Homework Statement We need to fin the initial velocity of a water fountain. The data I have collected is: Height (bottom to apex)= 0.042 m Distance (from spout to end on the stream)= 0.112 m Time (it takes to travel)= .25 seconds Angle the water shoots from= 50 degrees Here is more if it...

I'm trying to figure our the relation between cross section, scattering angle and KE? I'm doing a few exercises where I've been given kientic energy and scattering angle and have to calculate the cross section. Cross section is in units of Barns (m2), and KE is 1/2 kg*m2*s-2, but I can't seem...

Homework Statement An archerfish hunts by dislodging an unsuspecting insect from its resting place with a stream of water expelled from the fish's mouth. Suppose the archerfish squirts water with a speed of 2.00 m/s at an angle of 50 degrees above the horizontal, and aims for a beetle on a...

Calculate the sides of a triangle knowing its area, perimeter and angle A. Area = 30 m2 Perimeter = 30m Angle A = 30º NOTE = You can use the online triangle calculator TrianCal to see and draw the results. NOTE = Do not use the values ??of responses. A) 6.09, 9.36 and 14.55 B) 7.40, 8.63 and...

In a plane we have :$\overline {AB}=\overline {BC}=\overline {CA}=\overline {CD}=10$ and $\overline {AD}=11$ find :$\angle ADB=?$

Hi. I've been reading about Compton scattering and I don't understand what determines the angle at which the electron and photon are scattered. Is it a quantum process, and therefore the value of the angle is "random"? If it is a quantum process, is there any theory that gives the probability...

what would be the angle of a arms and how it is to be determined

Suppose I am on ISS and Earth is exactly below (at the right angle to the ISS's line of path). Now if I throw one ball below towards Earth from window at exactly 90 degrees to the line of path of ISS and one ball upwards at right angle to the line of path of ISS. **Assume normal human strength...

Homework Statement whats the minimum angles to the vertical(theta) for a projectile(ball) to be realeased with speed v such that at any point of time the distance to the ball is increasing. Homework Equations Sh=vtsin(theta) Sv=vtcos(theta)-0.5gt^2 The Attempt at a Solution so i used...

Homework Statement Homework Equations αt = r α The Attempt at a Solution ωi = 0 rad/s αt = 2.00 rad/s2 r = 112 m θ = ? at a = 6.80 m/s2 I'm not exactly sure where to begin. Help is appreciated.

Homework Statement 9.12) The mass of the box on the left is 30kg and the mass of the box on the right is 40kg. The coefficient of static friction between each box and the inclined plane is μs = 0.2. Determine the minimum angle α for which the boxes will remain stationary. Homework Equations...

Hi, Concerning optical polarization, what is the Jones Matrix of a mirror at a non-zero angle of incidence with respect to incoming light? For a mirror at normal incidence the matrix is (1 0; 0 -1); How do I incorporate the angle?

A box weighing 87 lb is being pulled with a rope that exerts a force of 60. lb at an angle of 15 degrees with the horizontal. If the coefficient of kinetic friction is .35, what is the kinetic friction?

According to Daniel Gillespie in A Quantum Mechanics Primer (1970), " . . . any observable which in classical mechanics is some well behaved function of position and momentum, f(x,p), is represented in quantum mechanics by the operator f ( \hat{x} , \hat {p} ) . That is, a = f (x,p) . . ...