Name: balancing weight with magnetic force
Uploaded: 2025-05-22T09:05:51.000Z
Duration: 1 min 22 s
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K12 Standards

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North Carolina K-12 Science Standard Course of Study

9-12

Physical Science

motion-and-stability-forces-and-interactions

Motion and Stability- Forces and Interactions

PS.PSc.6.4

magnetic-force-on-current-carrying-wires-example

Magnetic Force On Current-Carrying Wires: Example

Considere un conductor en el plano XY que lleva corriente hacia la izquierda. El conductor consta de dos segmentos rectos con una longitud de L paralelos al eje x y un semicírculo con un radio de R.
Si el conductor está colocado en un campo magnético uniforme perpendicular al plano del cable, apuntando hacia afuera, determine la fuerza magnética total sobre el conductor.
En primer lugar, determine la fuerza magnética para las secciones rectas individuales que transportan corriente en la dirección x.
En segundo lugar, divida el segmento curvo en secciones rectas infinitesimales que tengan una longitud de dl en un ángulo de theta.
La longitud infinitesimal y el campo magnético son perpendiculares entre sí, y la dirección de su producto cruzado es radialmente hacia afuera. Por lo tanto, se pueden determinar la magnitud y los componentes de la fuerza en las secciones.
Al integrar la expresión con respecto a theta, se puede determinar la fuerza en todo el conductor curvo.
Finalmente, al sumar las fuerzas en las tres secciones, se puede obtener la fuerza total sobre el conductor en la dirección y positiva.

<ol>
	<li>OpenStax. (2019). Física Universitaria Vol. 2. [Versión web], págs. 396 - 398. Obtenido de <a href="https://openstax.org/books/university-physics-volume-2@8ede2ba/pages/11-4-magnetic-force-on-a-current-carrying-conductor">https://openstax.org/books/university-physics-volume-2@8ede2ba/pages/11-4-magnetic-force-on-a-current-carrying-conductor</a></li>
</ol>

fuerza magnética en cables que llevan corriente: ejemplo

En un campo magnético, las cargas en movimiento encuentran una fuerza. Si un cable contiene estas cargas en movimiento, es decir, si el cable lleva corriente, entonces también actúa una fuerza sobre el cable. Considera un par de cables flexibles que sostienen un cable de 40 cm de largo y 10 g de peso en posición horizontal. El cable se coloca en un campo magnético constante de 0.40 T, como se muestra en la Figura 1(a). Determina la magnitud y dirección de la corriente que fluye por el cable necesaria para eliminar la tensión en los cables de soporte. Primero, para resolver el problema, dibuja un diagrama de cuerpo libre del sistema, como se muestra en la Figura 1(b). Segundo, utiliza la regla de la mano derecha para determinar la dirección de la fuerza magnética que actúa sobre el cable. Finalmente, iguala las dos fuerzas para determinar la corriente en el cable. <img alt="Equation1" src="/files/ftp_upload/13769/13769_Figure_1.png" style="text-align: center;"> En un diagrama de cuerpo libre, la tensión en los cables de soporte es cero cuando las fuerzas magnéticas y gravitacionales están equilibradas. Al utilizar la regla de la mano derecha, la fuerza magnética apunta hacia arriba, y al igualar las dos fuerzas de peso y fuerza magnética en el cable: <img alt="Equation2" src="/files/ftp_upload/13769/13769_Equation_2.svg" style="text-align: center; height: 20px;"> <img alt="Equation3" src="/files/ftp_upload/13769/13769_Equation_3.svg" style="text-align: center; height: 50px;"> La corriente en el cable se puede determinar. El campo magnético grande crea una fuerza significativa en una longitud de cable para contrarrestar el peso del cable.

Fuerza magnética en cables que llevan corriente: Ejemplo

En un campo magnético, las cargas en movimiento se encuentran con una fuerza. Si un cable contiene estas cargas móviles, es decir, si el cable transporta una corriente, entonces una fuerza actúa ...

Education

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JoVE Core

Physics

Física

Unit 1

Unidad 1

Magnetic Forces and Fields

Fuerzas y campos magnéticos

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

balancing weight with magnetic force

Magnetic force can balance the weight of a current-carrying wire when the wire sits in a magnetic field. Moving charges in the wire feel a force, so the wire itself can be pushed upward or downward. This example uses a flexible wire that is 40 cm long and has a mass of 10 g. It is held in a horizontal position inside a constant 0.40 T magnetic field.

The goal is to find the current needed to remove the tension in the supporting leads. To do that, a free-body diagram is drawn first. The diagram shows the forces acting on the wire. Then the right-hand rule is used to find the direction of the magnetic force on the wire.

When the tension in the leads is zero, the magnetic force and the gravitational force are balanced. The magnetic force points up, so it can counter the wire’s weight. By setting the weight equal to the magnetic force, the current in the wire can be determined. The strong magnetic field produces a large enough force on the wire to support its weight.

Balancing Weight with Magnetic Force

magnetism

Magnetic Poles and Everyday Uses

Magnetism appears in many everyday objects, from toys and hangers to elevators, doorbells, and computer devices. Magnets have two poles, called north and south. Like poles repel each other, while unlike poles attract. Both poles can also attract unmagnetized iron. A single magnetic pole cannot be isolated, because every part of a magnet contains both a north pole and a south pole. A compass needle is a simple example of a magnet. It is a thin bar magnet suspended at its center, so it can turn...

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Reading Magnetic Field Lines

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Magnetic Flux Through Surfaces

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motion of a charged particle in a magnetic field

motion-of-a-charged-particle-in-a-magnetic-field

Charged Particle Paths in Magnetic Fields

A charged particle in a magnetic field follows a path that depends on the direction of its velocity. When the field is uniform and the particle moves perpendicular to it, the magnetic field is the main factor that controls the motion, especially in a vacuum. The magnetic force is always perpendicular to the direction of motion, so the particle curves into a circle. Because the force stays perpendicular to velocity, it does no work on the particle. The kinetic energy and speed stay constant...

magnetic force

Magnetic Fields and Moving Charges

Magnetic fields and moving charges create magnetic force. A moving electric charge, or a current made of many moving charges, produces a magnetic field. When another current or moving charge enters that field, it feels a magnetic force in response. At the atomic level, magnetic forces come from interactions between moving electrons in the atoms of two bodies. The strength of magnetic force depends on several factors. It increases with the size of the charge and with the strength of the...

magnetic force on a current-carrying conductor

magnetic-force-on-a-current-carrying-conductor

Current and Magnetic Field Around a Wire

A current-carrying wire creates a magnetic field around it, and moving charges feel a force in that field. Because the magnetic field produced by moving charges is proportional to current, the wire itself acts as a source of magnetic field. A compass placed near the wire shows this effect by lining up tangentially around the wire. The magnetic field around a straight wire forms concentric circular loops. The right-hand rule helps determine the direction of those loops. If the thumb points in...

magnetic force on current-carrying wires: example

Magnetic force can balance the weight of a current-carrying wire when the wire sits in a magnetic field. Moving charges in the wire feel a force, so the wire itself can be pushed upward or downward. This example uses a flexible wire that is 40 cm long and has a mass of 10 g. It is held in a horizontal position inside a constant 0.40 T magnetic field. The goal is to find the current needed to remove the tension in the supporting leads. To do that, a free-body diagram is drawn first. The diagram...

force on a current loop in a magnetic field

force-on-a-current-loop-in-a-magnetic-field

Current Loops and Torque in Motors

Current loops in a magnetic field create the torque that drives a DC motor. A DC motor converts electrical energy into mechanical work. In a motor, wire loops sit inside a magnetic field. When current flows through the loops, the magnetic field pushes on them and makes the shaft rotate. The current is reversed when the loop lines up with the magnetic field. This keeps the torque on the loop going in the same direction. A commutator and brushes handle this reversal. The commutator switches the...

torque on a current loop in a magnetic field

torque-on-a-current-loop-in-a-magnetic-field

Current Loop Torque in Electric Motors

Current loop torque in electric motors shows how magnetic force can make a wire loop rotate. In an electric motor, loops of wire sit between magnets in a magnetic field. When current flows through the loops, the field applies torque. This rotation turns a shaft and converts electrical energy into mechanical energy. A rectangular current-carrying loop with N turns in a uniform magnetic field has zero net force. Even so, it can still experience net torque. The torque depends on the current I,...

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Hall voltage and charge carriers are explained through Edwin H. Hall’s 1879 experiment. His setup helped identify the polarity of the main charge carriers in a conducting material. It also showed, for the first time, that the charge carriers in most metals are negative. A metal slab is placed in a constant magnetic field. The electrons move from right to left, so the magnetic force pushes them toward the top edge of the slab. This leaves excess negative charge at the top and excess positive...

thomson's e/m experiment

Electron Speed Selector in Thomson’s Tube

A velocity selector uses electric and magnetic fields to choose charged particles with one speed from a beam. Many beams from a heated cathode contain particles moving at different speeds, so this setup helps produce a uniform beam. The electric and magnetic fields are perpendicular to the particle’s motion and to each other. In this arrangement, a particle with charge q, speed v, and mass m enters from the top. The magnetic field points into the plane of the paper, and the electric field...

key terms and concepts

Find out how a current-carrying wire can be supported by a magnetic field. Use a free-body diagram and the right-hand rule to solve for current.

Balancing Weight with Magnetic Force | JoVE K12

physics

JoVE Core Física presenta la teoría y la aplicación de conceptos físicos fundamentales, como la cinemática, dinámica, mecánica de fluidos, estática, ondas y acústica, mediante animaciones audiovisuales concisas y fáciles de entender. Además, los vídeos de científicos en acción muestran la aplicación de los conceptos relacionados en experimentos de investigación clásicos y originales, realizados en laboratorios de todo el mundo.

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Ohio’s Learning Standards and Model Curriculum

Electricity And Magnetism

Electromagnetic interactions

Tennessee Academic Standards

High School

Energy

PHYS.PS3.9

Virginia  Standards of Learning

HIgh School

PS.9

PS.9.d

PH.7

PH.7.a

PH.7.b

Alabama Course of Study Science

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Waves and Their Applications in Technologies for Information Transfer

9-12.PS.2.3.b

Florida Department of Education

SC.912.P.10

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Balancing Weight with Magnetic Force

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