Magnetostatics
This law, in its integral form, states that the line integral of the magnetic field B around a closed loop is proportional to the total current enclosed by that loop
What is Ampere’s Law?
This law specifies that the direction of an induced electromotive force (EMF) will always act to create a current whose magnetic field opposes the original change in flux
What is Lenz’s Law
This essential equation describes the total force exerted on a particle of charge q moving with velocity v through both electric and magnetic fields
What is the Lorentz Force Law
This circuit element is defined by its ability to resist any sudden changes in the flow of electric current through it
What is an inductor
The Maxwell equation ∇⋅B=0 provides the physical conclusion that these hypothetical "single-poled" magnetic entities do not exist in nature
What are magnetic monopoles
This fundamental law provides the mathematical means to calculate the magnetic field generated by a small, infinitesimal segment of a current-carrying wire
What is the Biot-Savart Law
One of Maxwell’s core equations, it states that the line integral of the electric field around a closed loop is equal to the negative rate of change of the magnetic flux through that loop
What is Faraday’s Law of Induction
Because the magnetic force is always perpendicular to a particle's instantaneous velocity, magnetic fields are physically unable to perform this on a moving charge
What is work
The total energy stored within the magnetic field of an inductor is determined by this mathematical formula involving inductance L and current I
What is 1/2LI^2
A vector field is uniquely specified only if you define both its divergence and this other vector property
What is the curl
At a perpendicular distance r from an infinitely long straight wire carrying current I, the magnetic field strength is determined by this specific formula
What is μ0I/(2πr)
This phenomenon occurs when a changing current in one circuit induces an electromotive force across a second, separate circuit
What is mutual inductance
When two parallel wires carry electric currents flowing in the same direction, they will exert this specific type of force on one another
What is attraction
In a circuit containing a resistor and an inductor, this ratio—represented as L/R—dictates the time scale for current decay or growth
What is the time constant
Unlike magnetic field lines which always form closed loops, electric field lines in electrostatics must begin and end on these
What are electric charges
For a circular loop of wire with radius R carrying a current I, this is the resulting magnetic field strength at the exact center of the loop
What is μ0I/(2R)
This type of EMF is generated specifically when a conductor moves through a constant magnetic field, causing a redistribution of internal charges
What is motional EMF
A charged particle moving at a constant speed perpendicular to a uniform magnetic field will be forced into a trajectory of this geometric shape
What is a circle
To calculate the effective inductance of two inductors connected in this specific way, you simply add their individual inductances together
What is a series connection
James Clerk Maxwell modified Ampere’s Law by adding this term to account for magnetic fields produced by changing electric fields
What is displacement current
In an ideal version of this electromagnetic device, the magnetic field is essentially constant and uniform on the inside while being zero on the outside
What is a solenoid
This theorem proves that for any two circuits, the magnetic flux through the second caused by a unit current in the first is identical to the flux through the first caused by a unit current in the second
What is the Reciprocity Theorem?
This is how a commutator ensures continuous rotation in a DC motor.
What is periodically flipping the direction of the current in the armature loop, ensuring that the magnetic torque always acts to drive the motion rather than allowing the loop to simply align with the field and stop
In an oscillating LC circuit, energy continuously sloshes back and forth between these two specific types of fields
What are electric and magnetic fields
While the magnetic component of the Lorentz force is mathematically incapable of performing work because it is always perpendicular to a charge's velocity, electromagnetic systems perform mechanical work by drawing from this
what is an external power source (like a battery) providing the energy, and redirecting the force of that charge