Sections
Glossary
Glossary
- Ampere’s law
- the physical law that states that the magnetic field around an electric current is proportional to the current; each segment of current produces a magnetic field like that of a long straight wire, and the total field of any shape current is the vector sum of the fields due to each segment
- B-field
- another term for magnetic field
- Biot-Savart law
- a physical law that describes the magnetic field generated by an electric current in terms of a specific equation
- direction of magnetic field lines
- the direction that the north end of a compass needle points
- gauss
- G, the unit of the magnetic field strength;
- Hall effect
- the creation of voltage across a current-carrying conductor by a magnetic field
- Hall emf
- the electromotive force created by a current-carrying conductor by a magnetic field,
- Lorentz force
- the force on a charge moving in a magnetic field
- magnetic field
- the representation of magnetic forces
- magnetic field lines
- the pictorial representation of the strength and the direction of a magnetic field
- magnetic field strength (magnitude) produced by a long straight current-carrying wire
- defined as where is the current, is the shortest distance to the wire, and is the permeability of free space
- magnetic field strength at the center of a circular loop
- defined as where is the radius of the loop
- magnetic field strength inside a solenoid
- defined as where is the number of loops per unit length of the solenoid with being the number of loops and the length)
- magnetic force
- the force on a charge produced by its motion through a magnetic field; the Lorentz force
- magnetic resonance imaging (MRI)
- a medical imaging technique that uses magnetic fields create detailed images of internal tissues and organs
- magnetocardiogram (MCG)
- a recording of the heart’s magnetic field as it beats
- magnetoencephalogram (MEG)
- a measurement of the brain’s magnetic field
- Maxwell’s equations
- a set of four equations that describe electromagnetic phenomena
- meter
- common application of magnetic torque on a current-carrying loop that is very similar in construction to a motor; by design, the torque is proportional to and not so the needle deflection is proportional to the current
- motor
- loop of wire in a magnetic field; when current is passed through the loops, the magnetic field exerts torque on the loops, which rotates a shaft; electrical energy is converted to mechanical work in the process
- north magnetic pole
- the end or the side of a magnet that is attracted toward Earth’s geographic North Pole
- nuclear magnetic resonance (NMR)
- a phenomenon in which an externally applied magnetic field interacts with the nuclei of certain atoms
- permeability of free space
- the measure of the ability of a material, in this case free space, to support a magnetic field; the constant
- right-hand rule 1 (RHR-1)
- the rule to determine the direction of the magnetic force on a positive moving charge: when the thumb of the right-hand points in the direction of the charge’s velocity and the fingers point in the direction of the magnetic field then the force on the charge is perpendicular and away from the palm; the force on a negative charge is perpendicular and into the palm
- right-hand rule 2 (RHR-2)
- a rule to determine the direction of the magnetic field induced by a current-carrying wire: Point the thumb of the right-hand in the direction of current, and the fingers curl in the direction of the magnetic field loops
- solenoid
- a thin wire wound into a coil that produces a magnetic field when an electric current is passed through it
- south magnetic pole
- the end or the side of a magnet that is attracted toward Earth’s geographic south pole
- tesla
- T, the SI unit of the magnetic field strength;