Magnetic Basics
These two poles always come together in magnets.
What are north and south?
This formula gives the magnetic force on a moving charge. **
What is F = qvB sinθ?
Shape of the magnetic field around a straight current-carrying wire.
What are concentric circles?
The quantity measuring how much magnetic field passes through a surface.
What is magnetic flux?
This law states induced current opposes the change in flux.
What is Lenz’s Law?
The fundamental cause of magnetism.
What are moving electric charges and electron spin?
When velocity is parallel to the magnetic field, the force equals this value.
What is zero?
This formula gives the magnetic field around a straight wire. ***
What is B = μ₀I / (2πr)?
The formula for magnetic flux. ****
What is Φ = BA cosθ?
If flux increases into the page, the induced field points in this direction.
What is out of the page?
The SI unit of magnetic field.
What is the tesla?
The path followed by a charged particle entering a magnetic field perpendicularly.
What is circular motion?
This device creates a strong, uniform magnetic field inside a coil.
What is a solenoid?
This law states that changing magnetic flux induces an EMF.
What is Faraday’s Law?
Motion of a charged particle entering a magnetic field.
What is helical (spiral) motion?
Three materials that are strongly magnetic.
What are iron, nickel, and cobalt?
This rule determines the direction of force on a positive charge.
What is the right-hand rule?
The formula for the magnetic field inside a solenoid. *
What is B = μ₀nI/l?
Three ways to change magnetic flux.
What are changing B, area, or angle?
A loop initially has zero flux. It is placed into a 0.50 T field perpendicular to its 0.20 m² area in 0.10 s. Find the induced EMF.
What is 1.0 V?
A loop of area 0.15 m² is tilted at 60° in a 0.80 T magnetic field. Find the magnetic flux.
What is Φ = 0.060 Tm²?
The formula for the radius of a charged particle’s circular path in a magnetic field.
What is r = mv / (qB)?
Increasing this quantity increases the magnetic field inside a solenoid.
What are current or number of turns?
This formula calculates induced EMF.*****
What is ℰ = −N*dΦ/dt?
A loop experiences a decrease in magnetic flux of 0.75 Tm² over 0.25 s. Find the induced EMF and determine the current direction using Lenz’s Law.
What is 3.0 V, with induced field opposing the decrease?