Angle Definition and 1000 Threads

I made a magnetic field detector. I used a small U shaped magnet transformer core and wound a coil on the bottom length. This was then mounted on a piece of one inch PVC plastic pipe. One red LED and one green led were then attached to the core. A opamp was used to amplify the signal...

Homework Statement A 35 mH inductor with 1.0 resistance is connected in series to a 20 µF capacitor and a 60 Hz, 40-V (rms) source. Calculate the phase angle. Homework Equations tan φ = (XL - XC) / R The Attempt at a Solution Solving for φ: φ = tan -1 [(XL - XC) / R] XL = 2πfL = 13.194 Ω...

I'm not clear on whether the coupling constant for strange to antidown is modified in the same way as for strange to down, i.e. multiplied by ##\sin(\theta_C)##. And are the coupling constants of interactions mediated by Z also dependent on the Cabibbo angle? And what happens if you have say a...

Homework Statement A 165N sled is pulled a distance of 205m. The task requires 5200J of work to overcome friction and is done by pulling a rope at what angle? Coefficient of friction is 0.25. Homework Equations W= Fdcos@ (@ for theta) F= ma The Attempt at a Solution My free body diagram had...

Sorry i have question for TM polarization. i don't understand why if the angle < brewster's angle,then the reflected light will experience an pi phase shift? can anybody explain why?

To find the firing angle to hit a target at a given distance using the initial velocity and gravitational acceleration, we use the formula: Angle = Firing XDist = Distance the target is from the gun along the X axis YDist = Distance the target is from the gun along the Y axis Angle =...

Here is the Problem Here is the construction, Hoping that I have done it correct "State with reasons that $\angle$ ACB is bisected by line OC" Many THanks (Party)

Homework Statement Water skiers often ride to one side of the center line of a boat, as shown in the figure (Figure 1) . In this case, the ski boat is traveling at 15 m/s and the tension in the rope is 90 N.If the boat does 3700 N of work on the skier in 54.8 m, what is the angle θ between the...

Homework Statement Find the angle Theta so that the system is in equilibrium Mass of each block: 2 Kg Mass of ring: 4π Kg Homework Equations Static equilibrium: Rotational equilibrium The Attempt at a Solution Static equilibrium: 2g + 2g + 4πg = Normal N = 4g + 4πg Taking...

I recently posted a question on similar line and got few good explanations as well. Still, I am unable to understand clearly. Hence I am going more specific this time. In the given picture taken from internet, friction force acting between an inclined plane and an object is defined as Fr = W x...

Homework Statement A particle is thrown in the angle pi/3 radian with speed 10m/S. Find the time of movement if the maximal height is equal to the distance of fall. Homework Equations v^2-voy^2=2gh The Attempt at a Solution 0-10^2*3/4=2*10*hmax hmax=3.75 v0x*2t=3.75 v0*cos60*2t=3.75...

Homework Statement Calculate the grating constant, d, given that theta = 172.01167 degrees, and that lambda = 447.2 nanometers. 2. Homework Equations d = mλ / sinθ where m is an integer that refers to the order of diffraction where λ is the wavelength where d is the spacing between two slits...

Hi there, Suppose we had a car going in a circle. We know that the turning angle(angle between the movement direction and the wheel axis) and the friction are connected, because friction determines the centripetal force and it determines the radius of the circle that we make with our car. I need...

Homework Statement Homework Equations The one in the middle with cot (big tetha) The Attempt at a Solution I have no ideea how he finds the limiting cases for V<v0; v0<V and for V> v0/sqrt (1-v0^2) . The problem is from Landau course for theoretical physics, volume 2: The Classical Theory...

Homework Statement I have a question that came up during a mechanics problem. (I put my question towards the end of the post) A particle slides on a smooth inclined plane whose inclination ##\theta## is increasing at a constant rate ##\omega##. If ##\theta(t=0)=0## at which time the particle...

Hi, Recently I came across this image in deriving an equation for angle of repose of an object in an inclined plane: "W" is the weight of the component which acts vertically down. "Rn" is the normal reaction by the inclined plane "W cos alpha" is the component of the weight of the object...

Homework Statement A point particle of mass m slides without friction within a hoop of radius R and mass M. The hoop is free to roll without slipping along a horizontal surface. What is the frequency of small oscillations of the point mass, when it is close to the bottom of the hoop...

I have a conceptual doubt. pl help me clarify it: What will happen if angle of incidence on a glass slab is 0? will refraction take place, or reflection, or both?

Homework Statement I just can't seem to find anything that I can relate to for solving this problem and it's giving me a headache. I don't even know how to start solving this question. Please help: A man drags a package across the floor with a force of 40 N. The mass of the package is 10 kg...

This is a kind of silly-sounding question I never realized puzzled me until moments ago, when I looked up the algorithm for spherical coordinates in n dimensions. In two dimensions, we have polar coordinates, consisting of r from 0 to ∞, and θ from 0 to 2π. In spherical coordinates, we have a...

Is angle a vector or a scalar quantity? (eg- θ in l=rθ)

What formula can I use to calculate the force I need to apply to a sliding arm that makes a point contact along the edge of a rotating arm attached to a shaft driving a load in order to push the rotating arm to rotate the shaft? The rotating arm is 1 cm wide. The load at the shaft is 1 Nm...

Homework Statement For the value of cos θ, determine the radian value of θ if π ≤ θ ≤ 2π. Value is -1/2. Homework EquationsThe Attempt at a Solution I got the first value which is cos-1(-1/2) which I got (2π)/3. However I am unsure how to get the second value. I thought that since the first...

Hi everyone ! I'm currently working on a project for which I need to measure the advancing contact angle of a liquid on a solid, specifically the advancing contact angle of a molten thermoplastic on carbon fibers. My understanding is that there is a difference between dynamic contact angles...

I'm trying to understand the solution to an exercise. The solution claims that that the absorbed power of a black body from sunlight with an angle of incidence of ##30^\circ## is ##P=P_0\cos(30^\circ)## The reasoning here being to take the component orthogonal to the surface. However what...

This is from a physics textbook, a chapter on rocket launch velocities, but really the question is how to integrate the first equation to get to the next. The way I was approaching it was like this: From ## V \frac{d\gamma}{dt}=-g \cos \gamma## Integrating from ##t=0## to some ##t##...

As you know, resistance of a rectangular shape is given by R=ρ A/L But how do we theoretically calculate the resistance of the bottom case? ( now, the current flow is not parrallel, current flows from bottom through the right side) I would like to know if there is any references for this...

Homework Statement A bird is able to go in a circle because it tilts its wings by theta degrees using a lift force, F. So it curves and eventually forms a full circle. if radius is 30m and the bird's velocity is 6m/s what is that tilt angle. Homework EquationsThe Attempt at a Solution I...

Homework Statement A small solid cylinder with mass m and radius r is attached to a larger cylinder with mass M and radius R resting on a horizontal surface. Jennifer wraps a string around the small cylinder and then applies a light tension to the string. If she holds the string vertically, the...

The question refers to the Feynman lectures on physics Vol I chapter 39. He discusses collisions between gas molecules. Here is a relevant extract: They are equally likely to go in all directions, but how do we say that? There is of course no likelihood that they will go in any specific...

Homework Statement Find the angle at which the projectile is launched. (Hint: use tan^2+1=sec^2) Initial Net Velocity=430 m/s The projectile lands perfectly on the edge of a cliff 80 meters high and 175 meters away. Homework Equations tan^2+1=sec^2 Kinematics, i.e.- v=vo+gt...

Homework Statement The problem asks me to evaluate the angle between these two lines: ##r : \begin{cases} x - 2y - 3 = 0 \\ 3y + z = 0 \end{cases} s : \begin{cases} x = 1 + 4t \\ y = 2 - 3t \\ z = 3 \end{cases}## both oriented to the decreasing ##y##. Homework EquationsThe Attempt at a...

Homework Statement The diagram represents a cylindrical aluminium bar AB resting on two horizontal aluminium rails which can be connected to a battery to drive a current through AB. A magnetic field, of flux density 0.10 T, acts perpendicularly to the paper and into it. In which direction will...

Homework Statement When a cart travel to the left at v=-10m/s, the angle of rain come towards it is 50o from normal. When the cart travel to the right at v=10m/s, the angle of rain water come is perpendicular to it. What is the angle of rain come to the earth? Homework Equations relative...

Homework Statement M1 and M2 are two masses connected as shown. https://loncapa2.physics.sc.edu/res/msu/physicslib/msuphysicslib/09_Force_and_Motion/graphics/prob75_fricpullplane.gif The pulley is light and frictionless. Find the mass M1, given that M2 (3.50 kg) is moving downwards and...

Hey, so I just finished taking a physic's test and one of the question was interesting to me. I thought it was pretty simple but my friend did the problem a different way, so I'm wondering what's the correct way to do this problem. So a box is moving down a frictionless ramp and onto the floor...

1.Question: A penguin is going down a slide. The coefficient of kinetic friction between the penguin and the slide has a value of 0.77. It takes three times as long to slide down this slide as it would if the slide were frictionless. Find the angle of the slide. 2. My answer: I chose solving it...

Homework Statement As shown in the figure below, a cuboid with uniform density is tilted by hand so that one edge remains in contact with a roughly surfaced floor. The angle of tilt, θ , is gradually increased, and when becomes larger than θ0 , the cuboid leaves the fingers and rotates. As...

In one of the experiments I give to my students, they need to set a burning candle at different (fixed) angles. In the past they have taped the candle to a cup and a needle taped to the cup like in the following picture. This is quite inefficient because for the same angle they need to tape and...

Homework Statement A force F is applied to a box of mass M at an angle θ below the horizontal (see figure). The coefficient of static friction between the box and the floor is μs, and the coefficient of kinetic friction between the two surfaces is μk. a) What is the minimum value of F to get...

Homework Statement At a construction site, a small crane is raising two boxes of nails on a plank to the roof. One box has already been opened and is half full, while the other box is new. The boxes, including the nails weigh 10kg and 20kg, respectively, and are the same size. If the...

Question: A kicker on a football team attempts to kick a field goal from 35 yards. The attempt just clears the goal post that is 10 feet high. The football lands 8 feet behind the plane of the goal. What speed and angle was the football initially kicked? (Use acceleration of gravity as 32...

Homework Statement Find the directional derivative using ##f\left(x,y,z\right)=xy+z^2## at the point (4, 2, 1) in the direction of a vector making an angle of ##\frac{3π}{4}## with ##\nabla f(4, 2, 1)##. Homework Equations ##f\left(x,y,z\right)=xy+z^2##The Attempt at a Solution I found the...

Hi, I just want to double check my understanding of Power angle. Say you have a large network, and you have a bus with a small generator and a larger load on it. For power to be going into that bus from the rest of the network there has to be power angle between the bus and a bus(s) which power...

Here is a circle with center $O$ :cool: Its is given that $\angle ABD=50$ & to find the magnitudes of $\angle ACD$ & $\angle ACB$ Now what I know is (Nerd) $\angle ACD=50$ due to the inscribed angle theorem, Can you help me to find the other angle which I don't know how to find ,stating the...

Homework Statement (a) Find the directional derivative of z = x2y at (3,4) in the direction of 3π/4 with the x-axis. Give an exact answer. (b) Find the directional derivative of z = x2y at (3,4) in the direction that makes an angle of 3π/4 with the gradient vector at (3,4). Give an exact...

Homework Statement Here is a picture of the problem https://www.dropbox.com/s/2bps6ga2o4hjpgw/hw4.png?dl=0 For those who don't want to click the link, basically the problem wants me to calculate the surface brightness of a flat surface at any angle if the source function S = B(T), which is a...

Homework Statement FInd the angle theta between AB and AC. a-1.7m, b=1.3m masteringengineering.com says my answer is wrong. I'm not sure of any other way to do the problem. Please advise. Homework Equations A(3, 0, 0) B(0, -.75, 1.3) C(0, 1.7, 1.5) The Attempt at a Solution r(AC)=...

Hello PF's members I know a magnetic field doesn't work on charged particles if magnetic field being perpendicular to the velocity of the particles. also i know magnetic field doesn't work if a charged particle enters with right angle into the field. But suppose that a charged particle like...

Homework Statement Hi all, I have solved these problems just wanted to see if it's all ok problem 1: a trolley starts at the lowest point of a diagonal plane with a 20m/s speed. Its acceleration is 4m/s^2 going downhill, the trolley goes up then slows until it reaches 0 speed and then goes...