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## Why does DC current produce magnetic field?

In the DC motor design, electric current creates a magnetic field in the armature coil which reacts against the magnetic fields of the permanent magnets to twist the armature about its axis.

## What are the sources of magnetostatic fields?

The sources of the magnetostatic fields are the permanent magnets and constant electric currents. The essential laws of the magnetostatic fields are Biot- Savart’s law and Ampere’s law.

## Can current produce magnetic field?

Electric current produces a magnetic field. This magnetic field can be visualized as a pattern of circular field lines surrounding a wire. One way to explore the direction of a magnetic field is with a compass, as shown by a long straight current-carrying wire in.

## Does a DC current produce a magnetic field?

Direct Current (DC) from a battery (or the traction power of a subway or light rail) will also create a DC magnetic field. However, to the extent that the demand (load) on a DC electrical circuit will vary with time, so too will the frequency of the “Quasi-DC” field which it produces.

## What is J in magnetostatics?

Where ∇ with the cross denotes curl, J is the current density and H is the magnetic field intensity, the second integral is a line integral around a closed loop with line element .

## How magnetostatic fields are produced?

A magnetostatic field is produced by a constant current flow (or direct current). This current flow may be due to magnetization currents as in permanent magnets, electron- beam currents as in vacuum tubes, or conduction currents as in current-carrying wires.

## Can DC be transformed?

As mentioned before, transformers do not allow DC input to flow through. This is known as DC isolation. This is because a change in current cannot be generated by DC; meaning that there is no changing magnetic field to induce a voltage across the secondary component.

## Which is not a source of a magnetostatic field?

1. One of the following is not a source of magnetostatic fields: a. A dc current in a wire. b. A permanent magnet. c. An accelerated charge. d. An electric field Linearly changing with time. e. A charged disk rotating at uniform speed.

## Is it possible to produce magnetic field with DC current?

Yes, but you cannot use this field to induce current in any other conductor. Only a varying magnetic field can do that (to generate that you need varying current). You can use this unidirectional field in a way similar to how you can use permanent magnets. For example – closing and opening electromechanical relays.

## How is a magnetic field produced by a static current?

A steady magnetic field is produced by a static current not by a static charge. Hence moving charges in a magnetic field also experience a magnetic force. The Lorentz’s force equation facilitates to determine the force experienced by a charged particle in the presence of electromagnetic fields.

## How is the magnetic vector potential used in magnetostatics?

In a similar way, the magnetic vector potential allows for a more efficient way of formulating the equations of magnetostatics, as shown further below. Helmholtz’s theorem says that a vector field is defined (up to a constant) by its curl and divergence.