In Euclidean geometry, an angle is the figure formed by two rays, called the sides of the angle, sharing a common endpoint, called the vertex of the angle.
Angles formed by two rays lie in the plane that contains the rays. Angles are also formed by the intersection of two planes. These are called dihedral angles. Two intersecting curves define also an angle, which is the angle of the tangents at the intersection point. For example, the spherical angle formed by two great circles on a sphere equals the dihedral angle between the planes containing the great circles.
Angle is also used to designate the measure of an angle or of a rotation. This measure is the ratio of the length of a circular arc to its radius. In the case of a geometric angle, the arc is centered at the vertex and delimited by the sides. In the case of a rotation, the arc is centered at the center of the rotation and delimited by any other point and its image by the rotation.
Homework Statement
Derive the formula for the Doppler effect for a receiver traveling at an angle theta away from a planar source
Homework EquationsThe Attempt at a Solution
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I thought that we can assume that the wavelength has two components ##λ_x## and ##λ_y## where
##λ_x = ct+vtcosθ##...
Homework Statement
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After a completely inelastic collision between two objects of equal mass, each having an initial speed of v, the two move off together with a speed of v/3. What is the angle between their initial directions.Homework Equations
Conservation of momentum in both x and y...
Homework Statement
The problem states that there is a father pulling a 100 lb sled with a force of 100 lb at some angle. At what angle does the father have to pull in order for the sled to accelerate at 25 ft/s^2? The coefficient of kinetic friction here is given as 0.04.
Homework Equations
F...
I am trying to understand how a blazed diffraction grating works and came across a deduction I don't understand. I believe that you don't need to know much about optics to answer this question as it is more geometry related.
I have the diagram below of a diffraction grating with all the relevant...
Homework Statement
A 75 kg man stands on a 8meter 25kg ladder at 6 meters above the bottom when it just starts to slip. Mu(s) is.3. What is the angle of the ladder?
ladder mass=25kg
ladder length=8m
man mass= 75kg
radius of man slipping = 6m
Mu=.3
angle= ?
Homework Equations
F= Mu x Normal...
Homework Statement
A) For a steel ball rolling down a 35 degree slope from a height of .5 m above the table, how far will the ball travel in the x direction if it launches horizontally from the table which is 1m high
For the same ball rolling down a 45 degree slope from one meter high, what...
<Moderator's note: Moved from another forum and thus no template.>
I have a project from my Mechanics class which consist on building the system on the picture. It has a spring, cable and a protractor. I have to do an approximation of the mass and weight of the object that is put in the...
Ok, So with this problem it says to use double angle or half angle formula. I have the formulas in my notes just not sure how to apply them to the problem I feel like I should be using the double formula though. Here's the problem:
cos(2*theta)+sin^2=0
I'm a teacher at a Senior High School in Indonesia. I have two Senior High School physics books (Indonesian book) written about simple harmonic motion formula:
y = A sin θ = A sin (ωt + θ0) = A sin 2πφ = A sin 2π (t/T + θ0/2π)
phase angle = θ = ωt + θ0
phase of wave = φ = t/T + θ0/2π
But I...
Homework Statement
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2. Homework Equations
Fs = Nμ
W = mg
Fy = Fsin(θ)
Fx = Fcos(θ)
The Attempt at a Solution
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Hello all at PhysicsForums,
I have a question on angled force and static friction. From my attempt below, I think I have found the maximum force required and would need...
Homework Statement
Projectile motion
I have an an object that is shot at an angle of 55 degree's. (the velocity listed next to it was 35 m/s, which was not listed as Vo but I think I have to assume it is?) It is launched from the ground. it is meant to land to hit a button that is elevated by...
Homework Statement
A pole stands 75 feet tall. An angle θ is formed when wires of various lengths of ##x## feet are attached from the ground to the top of the pole.
Find the rate of change of the angle ##\frac{dθ}{dx}## when a wire of length 90 ft is attached.
Homework EquationsThe Attempt at...
Homework Statement
A capacitor is made up of a pair of square plates, each of side length L, that are very nearly parallel (such that θ is very small) and separated by a distance D. The plates make an angle, θ, with one another. The capacitor may be thought of as being comprised of many...
Homework Statement
If I have the following relation:
tan(2x) = (B/2) / (A - C)
but tan(2x) = sin(2x) / cos(2x)
How do I obtain an expression for sin(x) and cos(x) in terms of the constants, B,A,C only?
Homework Equations
cos(2x) = 1- 2 sin^2(x)
The Attempt at a Solution
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I can't...
I would like to convert my joystick's two axis float (horizontal and vertical) to a 360 angle that can be used to set a players direction in my game. From my research, I've found the best route to take is using Atan2.
Variables:
self.rot = 0
horaxis = joy1.get_axis(0)
veraxis = joy1.get_axis(1)...
Homework Statement
Light of free-space wavelength λ0 = 0.87 μm is guided by a thin planar film of thickness d = 3.0 μm and refractive index n1 = 1.6, surrounded by a medium of refractive index n2 = 1.4
critical angle = 61.04°
n0 = 1.00
(a) Determine (i) the angle of incidence θ and (ii) the...
Homework Statement
A climber with mass m=54.4 kg has reached the top of the l=15.70 m climbing wall, and then is lowered straight down by the belaying person without touching the wall. Assume that at the top the rope is going through the pulley, while to the belaying person the rope is inclined...
Homework Statement
Forces of 11.8N north, 19.2N east, and 15.9N south are simultaneously applied to a 3.93kg mass as it rests on an air table. What is the magnitude of its acceleration?
What is the direction of the acceleration in degrees? (Take east to be 0 degrees and counterclockwise to be...
Homework Statement
Find v(θ), the dependence of the speed of the object on the angle θ. The string is ideal and there's no friction.
Homework Equations
-
The Attempt at a Solution
I'm quite sure I should use the conservation of energy mgh = mv2/2, but I don't know how to express h with the...
Homework Statement
launch angle of θ=41.86°. The distance to the wall is d=11.06 m, and it strikes the wall with speed that is a fraction f=0.925 of the initial speed, while it is still gaining height (i.e., it has not the highest point of the trajectory). What is the initial velocity? Express...
Homework Statement
Vectors A and B have equal magnitudes of 4.93. If the sum of A and B is the vector 6.79j, determine the angle between A and B
Homework Equations
c^2 = a^2 + b^2 -2abcos(theta)
The Attempt at a Solution
I just rearranged the formula above so that I could solve for the...
Homework Statement
Instructions for finding a buried treasure include the following: Go 66.0 paces at 256deg, turn to 140deg and walk 125 paces, then travel 100 paces at 169deg. The angles are measured counterclockwise from an axis pointing to the east, the +x direction. Determine the resultant...
Homework Statement
Two vectors A and B have precisely equal magnitudes. For the magnitude of A + B to be 65 times greater than the magnitude of A - B, what must be the angle between them?
Homework EquationsThe Attempt at a Solution
I tried using the dot product and solving for the angle but i...
Homework Statement
A child in danger of drowning in a river is being carried downstream by a current that has a speed of 2.35km/h. The child is 0.505km from shore and 0.780km upstream of a boat landing when a rescue boat sets out. If the boat proceeds at its maximum speed of 18.8km/h relative...
Homework Statement
1-A rifle can shoot a projectile with a velocity of 207m/s. At what angle should the rifle be pointed to give the maximum range?
2-Evaluate the maximum range
Homework Equations
N/A
The Attempt at a Solution
I considered at first that the problem seemed like it could be...
Moved into a house with some solar panels facing due south and some facing due west. Our latitude is 33.8 North in California. We are in the Mojave desert with very little cloud cover. The angle of the roof is 22 degrees from horizontal.
What is the equation that will accept the azimuth and...
Homework Statement
A patrol boat off a coast is ordered to destroy a rocket launcher that sits on the roof of 40-meter tall building. The horizontal distance between the boat and the rocket launcher is 1500 meters. The muzzle velocity of the patrol boat’s stabilized 30-mm cannon is 141...
Hello,
in every book and on every website (e.g. here http://farside.ph.utexas.edu/teaching/315/Waves/node13.html) i found for driven harmonic osciallation the same solution for phase angle:θ=atan(ωb/(k−mω^2)) where ω is driven freq., m is mass, k is spring constant. I agree with it =it follows...
Homework Statement
A particle is moving clockwise in a circle of radius 2.50m at a given instant of time.
I have to find radiant and tangential acceleration and the speed of the particle.
The acceleration vector is 15.0 m/s² and the angle between the radius and the acceleration vector is 30°...
Homework Statement
An outfielder throws a baseball to his catcher in an attempt to throw out a runner at home plate. The ball bounces once before reaching the catcher. Assume the angle at which the bounced ball leaves the ground is the same as the angle at which the outfielder threw it as shown...
please help as I'm very old but play Pickleball which is similar to tennis but with a plastic whiffle ball and a solid racket on a reduced size modified tennis court. What I'm trying to figure out is the following: a player on the other side of the net and to the left of me returns the ball that...
Hi,
If 2 people are holding a bag at an angle of 45 degrees each, and then only person is going to hold it, it is being said that the force that will have to be applied by that one person will be 1.5 times greater than when he was applying it together with the other. Can anyone explain this or...
I am looking for a way to get, by a simple numerical computation, the 3 curves on the following figure:
For this, I don't know what considering as abcissa (comoving distance ?, i.e
##D_{comoving} = R(t)r##
with ##R(t)## scale factor and ##r## the coordinate which appears into FLRW...
Homework Statement
Problem 6.7[/B]
Radius of curve: 200m
Speed: 90 km/h=90000m/h
What should be the value of the banking angle if no dependence is to be placed on friction?Homework Equations
##F=ma##
##F_c=\frac {mv^2} {r}##
##w=mg##
Trig functionsThe Attempt at a SolutionI got an...
Homework Statement
If A = i + j + k and B = -i + -j + -k , then (A-B) will make angle with A? What is the concept behind it, could you please explain with a diagram? (this is the part from scalar and vector)
Homework EquationsThe Attempt at a Solution
If we substruct (A-B) we get '0' because...
Homework Statement
The resultant R of vectors P and Q is perpendicular to P and R=P both, then the angle between P and Q is what?
Now, what is the concept behind it? Could you provide me with an image of the resultant perpendicular to two vectors so that I can understand the concept and start...
Homework Statement
Homework Equations
Conservation of linear momentum
Conservation of energy
Energy-momentum relationship: ##E^2-(m_0c^2)^2=c^2p^2##
Lorentz transformation of energy: ##p=\gamma(v)(p'+vE'/c^2)##
##\mathbf{p}=\gamma(v)m_0v##, ##E=\gamma(v)m_0c^2##
The Attempt at a Solution
My...
A student ask me the question:
Why the other angles in Right angle triangle can't be more than 90 degrees?
I want to answer him correctly to the question, What Should I Say to Him?
Homework Statement
A light ray shines from a diamond (n = 2.42) into water (n = 1.33), and no refraction occurs. What is the angle of incidence?
0°30°45°60°
Homework Equations
sin θc = nr/ni ?
The Attempt at a Solution
I thought that by finding the critical angle then anything above that...
Hi,
I would like to implement voltage regulator based on microcontroller + triac.
I am able to calculate source RMS voltage by sampling signal using ADC, but don't know how to calculate triac angle to set desired RMS voltage.
For example i have 250v source RMS voltage and i need to calculate...
Homework Statement
A mobile disk of radius R and mass M is moving above another immobile vertical disk of the same radius.
Initially the mobile disk is at rest at the highest point above the immobile disk and then it starts rolling without slipping. Assuming the mobile disk never slips, find...
Hi, I'm making an electric longboard and trying to write an app for my phone to function as the remote. I've got a bunch of fancy Star-Trek-esque indicators on it, one of which is the pitch and roll of the deck. All the indicators have "danger zones" and turn red when they hit them, and for this...
Only recently started to understand Euler angles and rotation matrices, and I am reasonably comfortable with the concepts already posted here. I am pretty sure I am missing something obvious, but I cannot figure out the way to solve this problem:
A body in 3D space with a orientation defined by...
One sharp corner of a right-angled triangle is 50º. Calculate the angle between the raised height and the angle follower at right angles.
So I know that the angles are 90º, 50º and 40º. How do I find the angle between the raised height and angle follower?
Hi, I need a simple way to measure the maximum angle/vertical displacement of a 3D pendulum (weight hanging from a rope) undergoing random impacts. What will work?
This is my first post on this forum so sry if this is in the wrong place, but also it’s a weird question so I don’t know where it falls exactly.
Anyways my question is: when you have an angle, the further the distance is from the point where the angle forms, the distance between the two inner...
Homework Statement
for an assignment, we must investigate physics in context, my selected context is a log flume ride, focusing on the final slope. the height of the inclined plane is 13m, the hypotenuse is 17m and the horizontal length is 11m, calculated with a scale diagram and kinematics...