Angles Definition and 911 Threads

Hi guys, I had been wondering for a while why it is that we use the radian as the unit of angular measurement in higher sciences and mathematics (calculus, physics, engineering) as opposed to the degree. In reviewing the relationship between the degree and radian, I believe that I have...

First, I struggled with whether to put this in advanced or intro physics. I read the sticky, and since this is a 300 level class that is taken at the junior level in the physics BS program at my school, I put it here. If it's considered too simplistic for advanced physics, I apologize. I've...

Homework Statement Suppose a mountain is described by the function z = 10x^2 * y − 5x^2 − 4y^2 − x^4 − 2y^4 and that you are standing at the point (1,1,−2). The positive x-axis points east and the positive y- axis points north. If you walk in the northeast direction what angle above the...

Homework Statement Previous part of the question I have solved: Express cos(2x) in terms of sin(x): I got this answer: cos(2x)=1-2sin2(x) Hence or otherwise solve the equation cos(x) + 3sin(x/2) = 2 Homework Equations Double angle formulae: cos(2x)=cos(2x) - sin(2x)...

Car Truck Collisins w/ ANGLES! Homework Statement A blue car with mass mc = 431 kg is moving east with a speed of vc = 19 m/s and collides with a purple truck with mass mt = 1298 kg that is moving south with a speed of vt = 12 m/s . The two collide and lock together after the collision...

Homework Statement A weight of 5000 N is suspended by two cables. The object is at rest. The first cable is horizontal and the second makes an angle of 143 ° with the first cable. Find the tension of the first cable. Homework Equations Erm...I know it's something with sin or cosin...

I have 3 forces, I assume that the resultant is equilibrium, that is just a guess. a - 12N b - 5N c - 13N how do i calculate the angles between the forces. I think I have to use the cosine rule but am not really sure. I have a book Physics made Simple but it doesn't really help Alan

Using Mathematica, I need to define a discrete probability distribution of N equally spaced angles on the interval [0, 2Pi], which isn't exactly uniform. More precisely, I need the distribution to feature a "Poisson-like" behavior : the angles should be randomly selected by random "packs"...

We usually describe angles in two dimensions (x and y plane). What is the mathematics behind three dimensions?

I'm trying to figure out what formula to get started in this question: A 7kg bowling ball moving with a velocity of 8 m/s strikes a single pin of mass 1.36kg. The impact deflects the bowling ball 10 degrees from it's original path. The pin moves along a path 45 degrees from the original path...

I'm working on a programming project, and I've got this problem I don't really know how to describe or approach. Given a point and a number of lines extending from the point, I want to find the best angle (in 3d) to maximize the distances between the lines. The 2D equivalent would be to simply...

Homework Statement The question is as following: a) A dog in a stunt takes a jump off a rook which is 40 m high above the ground and lands on the next building which is of the same height , the gap between the two buildings is 6m @ the velocity of 8 m/s .Find the range of angles at which he...

There are two problems involving projectile motion and angles I am having problems with Homework Statement You are watching an archery tournament when you start wondering how fast an arrow is shot from the bow. Remembering your physics, you ask one of the archers to shoot an arrow parallel...

***Excuse the pluralization error in the title*** Homework Statement I attached a picture below...Homework Equations sin^2(theta)+cos^2(theta)=1 a^2+b^2=c^2 Vector properties Trig identities The Attempt at a SolutionI am familiar with trig identities and vector properties, but I can't...

Homework Statement Two crewmen pull a boat through a lock, as shown in Figure 5-25. One crewman pulls with a force of F1 = 115 N at an angle of θ = 36° relative to the forward direction of the raft. The second crewman, on the opposite side of the lock, pulls at an angle of 45°. With what force...

Homework Statement A crystal is heated from 0 to 100 degrees celcius, its lattice parameter 'a' increases by 0.17% due to thermal expansion. if we observe an x-ray reflection at a bragg angle theta= 19.3 degrees at 0 degrees celcius, by how much will theta change when the sample is heated to...

Hi Guys, need some assistance. I am sure what I am asking is trivial but i still need help. How could i find the angle within a spherical triangle (triangle formed on a sphere). Now this triangle has equal lengths on all 3 sides. Pleas help!

A snow-covered ski slope makes an angle of θslope = 29.0° with the horizontal. When a ski jumper plummets onto the hill, a parcel of splashed snow is thrown up to a maximum displacement of 1.70 m at θsnow = 19.0° from the vertical in the uphill direction as shown in the figure below. (a)...

Homework Statement a force is given by F= 20i - 60j + 90k N. Find its magnitude and the angles it forms with the coordinate axis. Homework Equations F = magnitude of F times the unit vector magnitude is square root (Fx squared + Fy squared + Fz squared) and the unit vector can be...

Hi! Yesterday i read and mostly understood that (cos(\theta) + isin(\theta)^{n} = (cos(n\theta) + isin(n\theta)

Homework Statement 62. In physics, it is important to use mathematical approximations. (a) Demonstrate that for small angles (<20°) tan a ~ sin a ~ a = (Pia'/180 degrees) where a is in radians and a' is in degrees. (b) Use a calculator to find the largest angle for which tan a may...

Homework Statement Giancoli 5th edition chapter 3 problem 38 a rescue plane wants to drop supplies to isolated mountain climbers on a rocky ridge 235m below the plane is traveling horizontally with a speed of 69.4m/s b) supposes, instead that the plane releases the supplies a horizontal...

i have a project where I need to measure 2 different angles and then take those 2 measurements and compute a final number. I was thinking about using inclinometers to do the measuring of the angles but am really stuck on what hardware/software to use. I was hoping to find something that is...

Homework Statement A small smooth ring R, of mass 0.6 kg, is threaded on a light inextensible string. One end of the string is attached to the fixed point A and the other end is attached to a ring B, of mass 0.2 kg, which is threaded on a fixed rough horizontal wire which passes through A...

Should I expect a frictional force to get bigger or smaller as an angle is increased?

How can the bond angle in a molecules are measured ? The methods used to measure the angles and length b/w bonds.

Hi, I have to measure a object as it goes up a incline. I have both X and Y angles, which is fine if the object travels perfectly up or down a incline. What I cannot figure out, is if the object travels (for lack of a better term) diagonally up a incline, how to figure out its total...

Hey all, I was hoping someone could explain to me how to calculate the angle between matrices, ie. two square matrices [ 2 0 0 -1] and [0 1 1 3^(1/2)] under the inner product <A|B> = trace (A^TB) Also, how would you go about determining an angle between...

hey, could someone tell me if it is possible to measure the angle of twist of a rigid shaft subjected to a torsional moment at one end by using eddy current testing?

2 ships, A and C are traveling on a parallel course, separated by some distance x. As their velocity is constant, I could say that they share an inertial frame of reference, or in other words are at rest wrt to each other. Their clocks have also been synchronised and I will assume for this...

I am trying to determine two dihedral angles for this polyhedron: http://georgehart.com/virtual-polyhedra/vrml/zonish-6-icosidodecahedron.wrl 1. The angle between a pentagon and a square? 2. The angle between a square and a triangle? This polyhedron is formed by adding squares...

My girlfriend is re-learning geometry. She has noticed that the sum of the angles of a triangle is equal to the measure of a straight angle and half the measure of a full revolution. She wants me to ask if there is any special relationship between a triangle and a straight angle or between a...

First off, i'd like to note that this isn't homework, and I've seen other threads in here that deal with question/equation/problems, so I hope this isn't against the rules. I found this on a practice physics test online. I'm just using it for the benefit of my knowledge, nothing more. I can...

Homework Statement Can someone please explain to me how parallax works? I don't understand how the angle of parallax is measured Question to help: Astronomers measuring the parallax angle to Planet X found that the angle measured after 6 months was 1.52 arcsec different from the initial...

To calculate the height of a crane which is on top of a building, dennis measures the angle of elevation to the bottom and the top of the crane. these were 62 degrees and 68 degrees respectively. if the building is 42 metres high find the height of the crane. I'm asking for a friend, excuse...

Hi guys, could you please help me out? Essentially, a laser is pointing at a certain point in 3 dimensional space. There is a fixed target that the laser is specifically supposed to point to. My job is to find the most efficient way to solve for the euler angles(yaw pitch and roll) in order...

Homework Statement A 0.045kg Steel marble collides obliquely with an identical stationary marble, and continues at 55 degrees to its original direction. The collision is perfectly elastic. What is the angle between the direction taken of the target (previously static) ball and the original...

Homework Statement Prove: cotAcotB=(cscB+cotA)/(tanAsecB+tanB) Homework Equations cotx=1/tanx, etc. I tried using pythagorean identities, like 1+cot2x=csc2x, and others, but I've been unable to solve the problem. The Attempt at a Solution Please help me out. The examples in my...

So I looked at a neat derivation for what the minimun escape velocity is, and It was pretty clever. Because this is conserved: KE + PE = 1/2 *mv^2 + -GMm/r You can find what the velocity would have to be to get to infinity with zero velocity 1/2 *mvesc^2 + -GMm/r = 1/2 *m(0)^2 +...

Hello, first timer here. not sure if this should be in physics section or not.. anywayss I have this question, 2-4 that i have to do for homework but i can't seem to set up the vectors in the correct way to solve b/c the axis/angles are really throwing me off. I'm new at this trying to learn...

Just to clarify the title... Basically for the below circuit we are required to find Vth, Rth and Vo. However, the method of solving this problem is a little strange to me, because as you can see, the source has a phase angle of 30 degrees. The solution to this problem basically says (to find...

A student showed me a problem, this week, it was: What is the number of regular polygons whose intern angle is an integer number? I used the equation i=180 (n-2)/n, where i is the internal angle of the polygon and n is the number of the sides of the polygon. After some trials, i got to the...

I have yet to see or understand the benefit of knowing the cosine and sine sum and difference of two angles identity... can someone please explain why you would want to break up one angle into two angles... then solve from there... does not make sense to me... just use a calculator.

Fairly straight forward question. If you have a set of three vectors specifying a frame of reference and a second set of 3 vectors stating another frame of reference. How do you get the Euler angles associated with that rotation? More generally I am considering the relative orientation of one...

In trying to compute deflection angles for photons given their impact parameter (closest distance of trajectory to centre of black hole if unaffected) I am trying to numerically integrate the following equation (d^2/d(phi)^2)(u)+u=3Mu^2. However I am stuck as to how to work out the initial...

How where all the possible tangents, cosines, and sines of angles found?

Homework Statement I am trying to find the angles (theta, phi) it is most probable to find the rigid rotor for the spherical harmonic m=1, l=1 Homework Equations The equation given is Y = (3/8pi)1/2*sin(theta)*ei*phi The Attempt at a Solution I have tried to solve it by...

Homework Statement A thin (1mg/cm^2) target of 48-Ca is bombarded with a 10-nA bean of alpha particles. A detector, subtending a solid angle of 2E-3 steradians, records 15 protons per second. If the angular distribution is isotropic, determine the total cross section, in mb, for the reaction...

Two horses on opposite sides of a narrow stream are pulling a barge along the stream. Each horse pulls with a force of 720N. The ropes from the horses meet at a common point on the front of the barge. What is the resultant force exerted by the two horses if the angle between the rope is 60o...

Homework Statement You are on a roller coaster ride, and enter the bottom of a loop of radius r moving at a velocity v0. You decide to measure your initial velocity v0 by using a simple bathroom scale and a little physics. As you go through the loop, the scale you are sitting on reads 5/2...