Magnetic Effect Of Electric Current Direct Current Dc

The magnetic effect of electric current is a process in which a current carrying conductor creates a magnetic field surrounding the conductor. This discovery made by Hans Christian Oersted plays a significant role in relating the two phenomena of electricity and magnetism. From straight conductor wire to coil and loop, the geometry of the conductor plays an important factor on the strength and patterning of the resultant magnetic field. It forms the foundation of a variety of devices including electromagnets, electric motors, and generators, that form the backbone of advanced technologies in Physics. Let's explore this topic in detail in the below article.

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This Story also Contains

1. Magnetic fields lines
2. Direction of Magnetic Field Lines
3. Strength of Magnetic Field Lines
4. Magnetic Effect Due to Flow of Current in Solenoid

Magnetic fields lines

Imaginary lines that are used to represent the magnetic field in a current-carrying conductor or a magnetic object are termed as magnetic field lines. These lines helps to understand the strength and direction of the magnetic field in space.

Direction of Magnetic Field Lines

Direction of magnetic field lines represents the direction of magnetic field at a given point. Magnetic field lines have certain orientations because the magnetic field is a vector quantity.

Outside a Magnet: These lines emerges from North pole and emerges from south pole of a magnet

Inside a Magnet: These field lines travel from the South Pole back to the North Pole, completing closed loops.

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Strength of Magnetic Field Lines

A magnetic field in the shape of concentric circles surrounds a straight current-carrying conductor. Magnetic field lines can be used to illustrate the magnetic field of a straight current-carrying conductor.

The direction of a magnetic field created by a current-carrying conductor is determined by the current's flow direction.

If the direction of electric current changes, the direction of the electric field reverses.

Assume a vertically hung straight current-carrying conductor is conducting an electric current from north to south, or from up to down. The magnetic field will be rotating clockwise in this circumstance. If the same current flows from south to north through the same conductor, the magnetic field will rotate in the opposite direction.

Magnetic Effect of Current due to circular loop

The magnetic field of circular loop current-carrying conductor is identical to that produced by a straight current-carrying conductor, and the current-carrying circular loop will act as a magnet.

Magnetic field lines in a current-carrying circular loop would be in the shape of concentric circles, and field lines would become straight and perpendicular to the plane of the coil at the center of the circular wire.

The Right-Hand Thumb Rule can be used to determine the direction of the magnetic field in a circular loop.

Right Hand Thumb Rule

It is a simple technique to determine the direction of the magnetic field produced around a current-carrying conductor.

"If you hold a current-carrying conductor in your right hand such that your thumb points in the direction of the electric current, the curl of your fingers around the conductor indicates the direction of the magnetic field lines."

Magnetic Effect Due to Flow of Current in Solenoid

A solenoid is a helical coil of wire that is tightly wound and has a small diameter in comparison to its length.

The current-carrying solenoid produces a magnetic field similar to that of a bar magnet. A solenoid's one end acts as a south pole, while the other acts as a north pole. A solenoid produces a parallel magnetic field, comparable to that of a bar magnet.

A solenoid's strong magnetic force can be utilized to magnetize a piece of magnetic material. An electromagnet is a magnet that has been formed in this way.

Properties of Magnetic Field Lines

The magnetic field lines have various unique characteristics, which are discussed further below.

1. The number of lines and their density determine the strength of magnetic field lines.
2. Magnetic field lines do not intersect.
3. Magnetic field lines are loops that continue indefinitely.
4. Arrows represent the direction of the field lines at any moment (south pole to north pole inside the magnet and north pole to south pole outside the magnet).
5. Near the poles, the density of field lines is very high.