Net Definition and 1000 Threads

I have been unable to determine whether a Halbach Array of permanent magnets would experience a net force in a uniform magnetic field.

This is an example given in my textbook: "On a frictionless horizontal surface, you push with a force ##\vec{F}## on a book of mass ##m_1## that in turn pushes on a book with a mass ##m_2##. What force does the second book exert on the first?" First they calculate the acceleration of book 2...

Homework Statement A 6.50 kg block is placed on an inclined surface. The coefficients of static and kinetic friction between the block and the surface are 0.685 and 0.485, respectively. The incline makes an angle of 18.8° relative to horizontal. The block is at rest and remains at rest. What is...

Homework Statement Consider a high voltage direct power line which consist of two conductor suspended 3 meters apart. The lines are oppositely charged, If electric field halfway between them is ##15000N/C## how much is the excess positive charge on a 1 km length of positive conductor ...

Homework Statement a) What is the magnitude of the net gravitational force on the m2=10kg mass? Assume m1=20kg and m3=15kg. b) What is the direction of the net gravitational force on the m2=10kg mass? Assume m1=20kg and m3=15kg. Homework Equations F = G*m2*m3/R^2 The Attempt at a Solution M2...

Homework Statement A child is initially sitting near the outer rim of a revolving merry-go-round. Suddenly, the child moves towards the center of the merry-go-round (while it is still revolving). For the merry-go-round+child system, let the symbols L and K refer to the magnitude of the angular...

A long horizontal wire carries 22.0A of current due north. What is the net magnetic field 20.0 cm due west of the wire if the Earth's field there points downward, 40 degrees below the horizontal, and has magnitude 5.0 E-5 T? My approach: 1. Drew north to the right and the wire lying flat, with...

Homework Statement So this was a problem worked in class by the professor in class. Find the net electric field at the origin due to the arcs Homework Equations L=2πr/4 λ=q/L E=kQ/r2 The Attempt at a Solution So the professor gave the answer using the fromula...

Homework Statement Homework Equations E=kq/r2 The Attempt at a Solution So i decided to do decouple the x and y values to make it simpler For Ex It became apparent through the geometry and charges that there would be no net field in the x direction For Ey: k/r2*...

Homework Statement Hello PF, I need some help with the assignment given: v=18-2t^2 m/s, where t is in second. When t= 0 the position of the particle is s_0 = - 3 m. For the first 5 seconds. Determine the total distance ( i got it to 65,33 ft) and the net displacement Δs, and the value of s at...

Good afternoon, I am currently trying to unnderstand Community Solar projects. I know how it works in the US and Europe but in our country the regulation of Net Metering does not exist. Can I find someone in the community who has thought about connecting retail clients or industrial clients...

Homework Statement An electric field given by https://edugen.wileyplus.com/edugen/shared/assignment/test/session.quest2560893entrance1_N10030.mml?size=14&ver=1486488694211 =...

Homework Statement Homework Equations σ=q/(4πr^2)→q=σ(4πr^2) E=q/(4πEod^2) E=(4πr^2σ)/(4πEod^2)The Attempt at a Solution So the first thing that i could include was that the point p was inside Shell 1 and therefor would not be affected by Shell 1. So it should be a fairly simple plug in the...

Homework Statement Homework Equations Enetx=((kq1)/r^2 +^2) with the pos/neg of the coefficients being dependent on the position of the charges around the point The Attempt at a Solution As everything is one dimensional we can assume the j an k compnents of the electric field are 0 Part a...

Homework Statement Figure (a) shows charged particles 1 and 2 that are fixed in place on an x axis. Particle 1 has a charge with a magnitude of |q1| = 19e. Particle 3 of charge q3 = +16e is initially on the x axis near particle 2.Then particle 3 is gradually moved in the positive direction of...

Homework Statement A dipole with charges ±q and separation 2a is located a distance x from a point charge +Q, oriented as shown in the figure. Part A: Find an expression for the magnitude of the net force on the dipole in the limit x≫a. Part B: What is the direction of the net force...

Homework Statement Homework Equations L=pi*r/2 λ=q/L Enet=∑λ(2sinθ)*kThe Attempt at a Solution So first to calculate L for each arc L1=pi(.107m)/2 L2=pi(.214m)/2 L3=pi(.321m)/2 and lambda: λ1=3.3E-6/L1=2E-5 λ2=-12E-6/L2=-3.9E-5 λ3=29.7E-6/L3=5.9E-5 So using θ=pi/2 and rearranging the...

Homework Statement Given that q = 20 µC and d = 11 cm, find the direction and magnitude of the net electric force exerted on the point charge q1 below. Homework Equations F(elect) = k (q1,q2)/d^2 The Attempt at a Solution 1. after converting each unit to its appropriate form, F(net...

Homework Statement Problem # 4:[/B] A thin semicircular rod has a total charge +Q uniformly distributed along it. A negative point charge -Q is placed as shown. A test charge +q is placed at point C. (Point C is equidistant from -Q and from all points on the rod.) http://imgur.com/AeVfddb Let...

1. You tow a plankton net submerged just below the surface of the Pacific Ocean for 100 meters. How many liters of seawater is filtered through the plankton net? 2. You count 50 copepods in 1 mL of the plankton net's collection vial. A. Estimate the number of copepods in the entire collection...

Hi. According to Lenz's law, a conducting ring responds to an increasing external magnetic field with a repelling field and to a decreasing external magnetic field with an attracting one. Thomson's experiment uses an AC coil, so its field strength changes between increasing and decreasing a...

Homework Statement a) Find the net force on charge 1. b) What is the net electric field acting on charge 1? Please see the attached files to view the image that goes with the questions above. Homework Equations I'm having trouble with this unit in general and I'm not to confident in these...

Suppose there is a black box resting on a flat surface, which surface is rigidly attached to the earth. Suppose inside the black box there is a process initiated which causes the black box to lurch to the right 3 centimeters and let's say after one second the box comes to a complete stop. (No...

Homework Statement What is the Net force (include direction) acting on charge Q2 due to Q1 and q? (ans: Fnet = 174N right) Homework Equations F=kQ1Q2/r2 E=F/QThe Attempt at a Solution I've figured out a) and b). It's just c) that's giving me trouble. I tried using the first equation - (9.0 x...

Homework Statement Homework Equations I can see how the net force is not the same but I'm not getting the net moment. The Attempt at a Solution 12mm x 10N = 120N-mm. How do these two FBDs not have the same net moments. Thanks for any help!

Homework Statement A 0.100-kg, 59.9-cm-long uniform bar has a small 0.055-kg mass glued to its left end and a small 0.100-kgmass glued to the other end. You want to balance this system horizontally on a fulcrum placed just under its center of gravity. no diagram given Homework Equations Στ = 0...

Homework Statement A merry-go-round has a mass of 1440kg and a radius of 7.50m . How much net work is required to accelerate it from rest to a rotation rate of 1.00 revolution per 7.00s? Assume it is a solid cylinder. Homework Equations I believe my relevant equations are: ICYL=½mr2 ω=(Δθ/Δt)...

Homework Statement An electric motor turns a flywheel through a drive belt that joins a pulley n the motor and a pulley that is rigidly attached to the flywheel. The flywheel is a solid disk with a mass of 80.0kg and a radius R = 0.625m. It turns on a frictionless axle. Its pulley has much...

Homework Statement To help reduce the severity of accidents, an engineering company designs large plastic barrels filled with antifreeze that can be placed in front of bridge supports. In a simple test, a 1200 kg car moving at 20 m/s [W] crashes into several barrels. The car slows down to 8.0...

Hi. Is the resistance of a charged cable different compared to a cable with zero net charge? If it is charged negatively, one could argue that now there are more carriers for the current, so the resistance should be smaller (similarly to water that becomes more conductive if ions are added). On...

I'm struggling with the concept of net work. If I had a box and was pushing it up an incline would the net work be all the forces parallel to displacement in x direction * displacement in the x direction added up, plus the displacement in the y direction * force gravity parallel to displacement...

Homework Statement Find the net force of water on the dam The dam has a width of w and the water is at a depth of d. So my question is, would you have to integrate ρgwd with respect to d? because the pressure is constantly changing every value of d. Homework Equations ρgwd ρ is the density of...

A stationary object resting upon the ground experiences two forces, the weight force as well as the normal reaction force of the ground. These forces sum to zero. The ground however experiences the weight force acting downwards upon it. What other force acts upon the ground to prevent it from...

Homework Statement A fuel gas consists of 75% butane (C4H10), 10% propane (C3H8) and 15% butene (C4H8) by volume. It is to be fed to the combustion chamber in 10% excess air at 25°C, where it is completely burnt to carbon dioxide and water. The flue gases produced are to be used to generate 5...

http://[PLAIN] [PLAIN][PLAIN]http://[PLAIN] 1. Homework Statement Calculate the net force acting on each object indicated in the following diagrams. (diagrams attached) I am working on "B" Homework Equations Sine Law: sin a/a = sin b/b = sin c/ c Cosine Law: c^2 = a^2 + b^2 -2ab*cos(c)...

SORRY TITLE SHOULD READ: "JUSTIFICATION FOR 0 NET E FIELD WITHIN A CHARGED SHELL" << Title fixed by Moderator (except for the all-caps of course) >>[/color] 1. Homework Statement A conceptual query: Considering an irregular shaped conducing shell with a net charge, using Gauss' Law, any...

Homework Statement [/B] A man pushes on a piano with mass 190 kg ; it slides at constant velocity down a ramp that is inclined at 17.0 ∘ above the horizontal floor. Neglect any friction acting on the piano. A. Calculate the magnitude of the force applied by the man if he pushes parallel to the...

Homework Statement Particle 1 of charge +4.0 μC and particle 2 of charge +1.0 μC are held at separation L=10.0 cm on an x axis. Particle 3 of unknown charge q3 is to be located such that the net electrostatic force on it from particles 1 and 2 is zero. In the included figure, particle 1 is...

Why is it so that the net work done by a force on an object is equal to change in kinetic energy only and not any other form of energy like potential energy? Also is the work energy theorem valid for both conservative and non conservative forces.

Homework Statement In a cubical volume, 1.05 m on a side, the electric field is given by the formula below, where E0 = 1.25 N/C and a = 1.05 m. = E0(1 + z/a) i + E0(z/a) j The cube has its sides parallel to the coordinate axes, see the figure. Determine the net charge within the cube...

Homework Statement Calculate the net force in Diagram B. Homework Equations Sine Law: sin a/a = sin b/b = sin c/ c Cosine Law: c^2 = a^2 + b^2 -2ab*cos(c) The Attempt at a Solution c^2 = (2N)^2 + (17)^2 -2(2)(17)*cos(45) = 16 N sin b/ 17N = sin45/16N = 49 degrees Fnet = 16 N (W 49 degrees N)...

Homework Statement Calculate the net flux (moles m^2- s^-1) of glucose molecules across a distance of 1um if the concentration difference is 100 mols m^3- and the diffusion coefficient for water is 5x10^-10 m^2 s^-1 Homework Equations so i used J=D(c1-c2)/DelaX The Attempt at a Solution I...

When there is a magnetic dipole placed in an external non uniform magnetic field, will it experience a net force?

Homework Statement Find the net torque on the wheel in the figure below about the axle through O, taking a = 13.0 cm and b = 31.0 cm. (Assume that the positive direction is counterclockwise.) pic...

[mentor note: moved here from another forum, hence no homework template.] A construction worker attempts to lift a uniform beam off the floor and raise it to a vertical position. The beam is 3.00 m long and weighs 372 N. At a certain instant, the worker holds the beam momentarily at rest with...

Homework Statement The question is: A 2 kg particle is moving in the positive x direction with the speed of 5 m/s. As it passes the origin, a force F = (30 N - 2N/s*t)i is applied to it. Where does the particle come to a stop? Homework Equations F=ma W = integral F(x)dx K=.5mv^2 The Attempt...

Hi, Newton's 2nd Law states that when a net force acts on a body, it causes acceleration in the body...This is well for forces acting on bodies in space...But what about on Earth??...On Earth when you apply force to an object, the air around it pushes back with same force!, So where is the...

In a linear isotropic homogeneous dielectric, P= χε0*E, where E is the net electric field from the effects of both free and bound charges. But E=(σfree—P)/ε0 So E itself depends on P. My concern is, isn't this circular? How can the polarization density depend on a field that itself depends...

Two stars of equal mass M move with constant speed V in a circular orbital of radius R about their common center of mass .What is the net force on each star?the answer to this question was net force=GM^2/4R^2 .I want to ask that why net force not equal to zero although it is in translational...

Dear all, I'm trying to think about applying the second law of thermodynamics to a system which is not isolated, but has an energy flowing inwards and an equal (!) energy flowing outwards, such that the total energy does not change (total energy flux is zero). Can we still apply the second law...