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Effects of a Uniform Magnetic Field on a Current on a Current Loop

Magnetic Field 

A magnetic field is a vector field in the presence of a magnet, an electric current, or a changing electric field in which magnetic forces may be observed. Magnetic fields, such as those found on Earth, induce magnetic compass needles and other permanent magnets to align in the field’s direction. Magnetic fields cause electrically charged particles to move in a circular or helical pattern. The functioning of electric motors is based on this force, which is exerted on electric currents in wires in a magnetic field. The magnetic field is stationary and referred to as a magnetostatic field when it surrounds a permanent magnet or a wire carrying a continuous electric current in one direction. Its magnitude and direction stay constant at any given place. The magnetic field around an alternating current or a fluctuating direct current is constantly changing in amplitude and direction.

Magnetic Field Lines 

Magnetic field lines are a visual depiction of the magnetic field’s unseen lines of force. The lines, by convention, trace the force from a magnet’s north to south pole. The gap between the lines represents the magnetic field’s relative intensity. The greater the magnetic field, the closer the lines are. The form, intensity, and direction of magnetic field lines may be traced using iron filings and a compass.

Properties

Extensive research into magnetic fields has uncovered a number of unbreakable laws. 

  • Magnetic field lines are used to illustrate the field (the lines are a pictorial tool, not a physical entity in and of themselves). These rules outline the characteristics of magnetic field lines:
  • The magnetic field’s direction can be seen tangentially to the field line, at any point in space. The field line will be shown by a little compass.
  • The field’s intensity is proportional to the proximity of the lines. It is proportional to the number of lines per unit area that are perpendicular to the lines (called the areal density).
  • Magnetic field lines can never cross, hence the field is unique at every location in space.
  • Magnetic field lines are infinitely long, producing closed loops with no beginning or end. They go from the north to the south poles.

Fleming’s right-hand Rule

According to Faraday’s law of electromagnetic induction, anytime a conductor travels inside a magnetic field, an induced current flows through it. There will be a relationship between the direction of applied force, magnetic field, and current if this conductor is pushed forcibly inside the magnetic field.

Fleming’s right-hand Rule determines the relationship between these three directions.

According to this rule, “Hold out the right hand with the first, second, and thumb at a right angle to each other.” If the forefinger indicates the direction of the force line, the thumb represents the direction of motion or applied force, and the second finger represents the direction of the induced current.”

Magnetic Due to flow of Current Through Circular Loop

Let us suppose that this straight wire is bent.

A current is sent through it in the shape of a circular loop. Magnetic induction occurs when electricity flows across a wire. A circle’s circumference is formed by field lines. It is well understood that the magnetic field generated by a current-carrying straight. The length of a wire is proportional to its distance from it. In the instance of a wire bent into a circular loop. The concentric rings indicating the magnetic field around a current-carrying circular loop would get larger and larger. The size increases as we walk away from the wire. 

By the time we get in the circular’s centre, The radius of curvature of circular magnetic field lines continues to increase in the loop. As a result, near the centre of the circle, the arcs of these large circles would be represented by straight lines. The magnetic field would be generated at every point on the wire carrying electricity, appearing as straight lines at the loop’s centre using the right hand rule; it is simple to ensure that each part is complete. Within the loop, the wire contributes to the magnetic field lines in the same direction.

The magnitude of the magnetic field B at the centre of the circular loop is given as:

B = ( μ0 I ) / ( 2 R ) 

Where μ0 denotes magnetic field permeability, I denotes current, and R denotes loop radius.

Conclusion 

A magnetic field is a vector field in the presence of a magnet, an electric current, or a changing electric field in which magnetic forces may be observed. Magnetic field lines are a visual depiction of the magnetic field’s unseen lines of force. The greater the magnetic field, the closer the lines are. Magnetic field lines are used to illustrate the field. These rules outline the characteristics of magnetic field lines: The magnetic field’s direction can be seen tangentially to the field line, at any point in space. The field’s intensity is proportional to the proximity of the lines. 

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Frequently asked questions

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