19.3 Physics Flashcards
When do charges experience the maximum magnetic force upon moving through a magnetic field?
When the charges move perpendicular to the magnetic field.
90 degrees
When do charges experience a lower in magnetic force upon moving through a magnetic field?
When it’s at any angle other than 90 degrees
And becomes zero when it’s 180
When do charges experience no magnetic force upon moving through a magnetic field?
When they move along the field lines (when the angle is 0.)
How can we describe the properties of the magnetic field B?
We can describe it in terms of magnetic force exerted on a positive test charge at a given point.
How do you find the magnitude of a magnetic field?
B = Fmagnetic/qv
What are the units of magnetic field, force, charge, and velocity?
Tesla (N/Cxm/s), Newtons, Coulomb, and meters per second.
i think these are the SI units
What’s the magnitude of most magnetic fields?
Less than 1T
What is the magnitude of some superconducting magnets?
30T
What’s Earth’s magnetic field near its surface?
It’s about 50 micro T (5x10^-5 T)
What is the alternative hand rule?
It’s a deviation from the original right hand rule that can be used to find the direction of the magnetic force.
Check page 674.
If the charge is negative rather than positive, which direction is the force pointed?
It’s pointed in the opposite direction of what’s in the alternative right hand rule.
Solve page 675
What’s the path that a charge follows upon going through a magnetic field?
It follows a circular path
The magnetic force is always directed toward…
*the center of the circular path *
Answer your questions page 676
The resultant force on a current-carrying wire equals what?
It equals the sum of the individual magnetic forces on the charged particles.
How is a magnetic field transmitted to the particles in a wire?
Through the collisions with the atoms making up the bulk of the wire
What’s the equation of force on a current-carrying conductor perpendicular to a magnetic field?
Fmagnetic = BIL
L = length of conductor within B
How do you use the right hand rule for a current-carrying conductor in a magnetic field?
By doing the same thing as you’d do normally, but placing your thumb in the direction of the current instead of the direction of velocity.
When the current is either in the direction of the field or opposite, the magnetic force on the wire is…
zero
When two conductors are parallel to each other, what is the direction of the magnetic field created by them?
One is perpendicular to the direction of the current of the other, and vice versa.
What happens to wires when the current in each is in the same direction?
They attract eachother
When the wires are in opposite directions, do they repel or attract eachother?
They repel
What do loudspeakers do to produce sound?
They use a magnetic force acting on a current-carrying wire in magnetic field to produce sound waves
The force between parallel conducting wires are always what to eachother?
Opposite
Solve page 678 and 679
