Expert Answers to Magnetic Force Equation Examples Right-Hand Rule and More!

Magnetic force on capacitor
I have this problem: I have a capacitor formed by two parallel square-shaped plates, of side $a$ , and with distance $d$ between them. They're asking me out of other things, the magnetic force as a function of some things. I calculate de magnetic force by calculating the gradient of the magnetic energy, given by:
$E = \frac{1}{2} ∭_{V} B \cdot H d V$
I have calculated $B$ and $H$ , that form, during the charge of the capacitor, loops around the center proportional to $r$ , being $r$ the distance from the central axis. The problem is that I have to integrate that to a cubic volume: $a^{2} d$ , one of those variables is independent, but the other two are not, and this problems never involve complicated integrals, such that one:
$\int_{0}^{a} \int_{0}^{a} r d x d y$
If the plates were circles it would be trivial, but being squares, I'm sure I'm missing something.

Taliyah Spencer 2022-05-03

Calculate magnetic field from magnetic force on a charged particle
The magnetic force, charge, and velocity of a particle are given. I am asked to find the magnetic field.
$q = - 2 μ C$
$\vec{v} = (- \hat{i} + 3 \hat{j}) \times 10^{6} m / s$
$\vec{F} = (3 \hat{i} + \hat{j} + 2 \hat{k}) N$
$B_{x} = 0$

tobeint39r 2022-04-30

Does protons moving parallel to each other exert magnetic force?
If two protons are moving parallel to each other in same direction with equal velocities then do they exert magnetic force on each other.? As protons are moving they should produce magnetic field and there should be some magnetic force + electric force on each of them. But if look from their refrence frame then both the protons are at rest and hence there will be no magnetic force (as magnetic field is created by a moving charge), only electric force on each of them. How can this be possible that force(magnetic force) on a particle becomes different on changing the reference frame even though the reference frames are non accelerating with respect to each other?

tiyakexdw4 2022-04-12

Work done by magnetic force
By Lorentz force law, $F_{m}$ is always perpendicular to velocity of charge $v$ . But $F_{m}$ is not necessarily perpendicular to the displacement of charge caused by $F_{m}$
Then how can we say that magnetic force does no work?
Edit:
One thing to clear: Is work done = displacement just before the force was applied dotted with force OR displacement just after the force was applied dotted with force? If the former were true, you would be correct. But if the latter were true, I don't see any reason why $F_{m}$ is perpendicular to the displacement just after the force was applied as there should be a component of displacement in the direction of force.

Damion Hardin 2022-04-07

Is Magnetic force different in different frames?
Suppose a charged particle moves with a velocity $v$ near a wire carrying an electric current. So, a magnetic force acts on it. If the same particle is seen from a frame moving with velocity $v$ in the same direction, the charge will be found to be at rest. Will the magnetic force become zero in this frame? Will the magnetic field become zero in this frame?
Even though the solution says that the force shall be zero but the magnetic field will be independent of frame and henceforth exist, I am not convinced with the idea of zero force because even if I were to place myself in a frame moving with velocity $v$ , I will see the particle executing a circular motion around a different center though. In reality I know that its the magnetic force that's causing it to move in a circle but in my frame if I say that there is no magnetic force, how would I explain the circular motion of the particle ?

lasquiyas5loaa 2022-04-07

How Can There Be Magnetic Force Without Velocity
Suppose there is a space with constant magnetic field, and a charged particle is moving in that space with a constant velocity, ofcourse it experiences a magnetic force and gets deflected.
But the particle it not necessarily moving wrt all frames. There may be some frame for which the particle doesn't move at all but still gets deflected. How is this possible, there must be some velocity for the particle to experience any deflection under influence of a magnetic field?
Also a still particle in the same space doesn't experience any deflection. True, but the same particle may be moving wrt to some other frame without experiencing a magnetic force, so here we have a velocity but no magnetic force case.
I remember I have used the relation $| F | = q v | B |$ a lot before, but I am afraid to use it any more, these things are really confusing.

Regina Ewing 2022-04-06

Mysterious magnetic force!
If you have a loop in which current goes clockwise as seen from top, then it forms a north pole if seen from below. Now if a particle with positive charge goes from left to right under it, it experiences and upward force, now if the 1st loop was very large and particle goes from near about the axis of loop, it goes in a circle in anti-clockwise direction as seen from the top. This again generates a north pole if seen from top.
Q1. Since we have two north poles facing each other, why don't we get a new repulsive magnetic force?
If you closely observe this systen then the negative charges travelling in 1st loop in anti-clockwise direction have synchronized with the positive charge going anti-clockwise below it. Not only this, if you send the particle from right to left, it experiences a downward force and again synchronizes, now again if you try sending negative particles they get synchronized in the same way with the positive particles.
Q2. Why is such a synchronizing taking place?
I am more interested in the first question for now, as I am trying to work out the second problem myself.

junoonib89p4 2022-04-06

Electric force vs. Magnetic force
$E$ , electric field $\to$ $H$ , magnetic field
$D$ , electric flux density $\to$ $B$ , magnetic flux density
$D = ϵ E$ $\to$ $B = μ H$
Electric force calculation is based on electric field: $F = q E$
But...
Magnetic force calculation is based on not magnetic field( $H$ ) but magnetic flux density( $B$ ):
$F = q v \times B$
What is the reason behind that? For magnetic force, why is magnetic flux density is used instead of magnetic field?

kdgg0909gn 2021-11-16

Boxes A and B are in contact on a horizontal, frictionless surface. Box A has mass 20.0 kg and box B has mass 5.0 kg. A horizontal force of 250 N is exerted on box A. What is the magnitude of the force that box A exerts on box B?

ankarskogC 2021-05-08

In the figure a worker lifts a weight $ω$ by pulling down on a rope with a force $\vec{F}$ . The upper pulley is attached to the ceiling by a chain,and the lower pulley is attached to the weight by another chain.The weight is lifted at constant speed. Assume that the rope,pulleys, and chains all have negligible weights.

A) In terms of $ω$ ,find the tension in the lower chain.
B) In terms of $ω$ ,find the tension in upper chain.
C) In terms of $ω$ ,find the magnitude of the force $\vec{F}$ if the weight is lifted at constant speed.

Josalynn 2021-03-21

In the figure below, the rolling axle, 1.43 m long, is pushed along horizontal rails at a constant speed $v = 3.36 m / s$ .

A resistor $R = 0.325$ ohm is connected to the rails at points a and b, directly opposite each other. (The wheels make good electrical contact with the rails, and so the axle, rails, and R form a closed-loop circuit. The only significant resistance in the circuit is R.) There is a uniform magnetic field $B = 0.0850 T$ vertically downward. Calculate the induced current I in the resistor and what horizontal force F is required to keep the axle rolling at constant speed?

Jaya Legge 2021-02-25

A stream of water strikes a stationary turbine bladehorizontally, as the drawing illustrates. The incident water streamhas a velocity of +18.0 m/s, while the exiting water stream has avelocity of -18.0 m/s. The mass of water per second that strikesthe blade is 17.0 kg/s. Find themagnitude of the average force exerted on the water by theblade.

abondantQ 2021-02-19

Two snowcats tow a housing unit to a new location at McMurdo Base, Antarctica, as shown in the figure. The sum of the forces $F_{A}$ and $F_{B}$ exerted on the unit by the horizontal cables is parallel to the line L, and $F_{A} = 4200$ N. Determine $F_{B}$ ? Determine the magnitude of $F_{A} + F_{B}$ ?

Lipossig 2021-02-11

Resolve the force F2 into components acting along the u and v axes and determine the magnitudes of the components.

Josalynn 2021-02-10

A frictionless plane is 10.0 m long and inclined atA sled starts at the bottom with an initial speed of 5.00 m/s up the incline. When it reaches the point at which it momentarily stops, a second sled is released from the top of this incline with an initial speed v1 both sleds reach the bottom of thein cline at the same moment.
(a) Determine the distance that the first sled traveled up the incline.
(b) Determine the initial speed of the second sled.

sibuzwaW 2021-02-08

A window washer of mass M is sitting on a platform suspended by a system of cables and pulleys. He is pulling on the cable with a force of magnitude F.The cables and pulleys are ideal (massless and frictionless), and the platform has negligible mass.
Find the magnitude of the minimum force F that allows the window washer to move upward.
Express your answer in terms of the mass M and the magnitude of the acceleration due to gravity g.

amanf 2021-02-08

A potters wheel having a radius of 0.50 m and a moment of inertia of $12 k g \cdot m^{2}$ is rotating freely at 50 rev/min. The potter can stop the wheel in 6.0s by pressing a wet rag against the rim and exerting a radially inward force of 70N. Find the effective coefficient of kinetic friction between the wheel and the wet rag.

BenoguigoliB 2021-02-05

Two adults and a child want to push a wheeled cart in thedirection marked x in Fig. 4.29 The two adults push with horizontalforces $F_{1} and F_{2}$ as shown in the figure. (a)Find the magnitude and direction of the smallest force that thechild should exerts the minimum force found in part (a), the cartaccelerates at 2.0 $\frac{m}{s^{2}}$ in the +x direction. What is theweight of the cart?

postillan4 2021-01-06

A marble moves along the x-axis. The potential-energy functionis shown in Fig. 1
a) At which of the labeled x-coordinates is the force on the marble zero?
b) Which of the labeled x-coordinates is a position of stable equilibrium?
c) Which of the labeled x-coordinates is a position of unstable equilibrium?

preprekomW 2020-12-03

A rectangular coil of wire, 22cm by 35 cm and carrying a current of 1.4A, is oriented with the plane of its loop perpendicular to a uniform 1.5T magnetic field.
a) calculate the net force and torque which the magnetic field exerts on the coil.
b)the coil is rotated through a 30 degree angle about the y axis, the left side coming out of the plane. Calculate the net force and torque which the magnetic field now exerts on the coil

Another interesting aspect of electromagnetism when you are exploring Physics or Engineering majors is dealing with the magnetic force equation. The majority of magnetic force, as you can see from the questions asked below, is related to the lab reports and the experiments. The answers will be verbal problems. See other magnetic force examples that will be written in the cause-and-effect assignment types. Certain answers will deal with the explanations. Both of the types will help you to solve your Physics challenges because you should learn more about the theory before you come up with an outline for your task.

Electromagnetism

Understanding Magnetic Force: Equation Examples Right-Hand Rule