Day 21

our group showing magnetic domains must be positioned in a metal that is made to be magnetic.

how to eliminate magnetism in a metal object that is magnetic.

mason is magnetizing a paperclip

after heating the paper clip, it is no longer magnetic.

no current through the pole

prediction when current is out of the box

prediction was verified

our predictions for what happens when magnetic fields interfere with each other.

showing how when the current carrying loop is in a magnetic field that the net force is always zero but that the net torque can still be something like in this case where the angle is 60 degrees.

showing the equation for torque.

showing how the torque is related to the angle of the plane

our calculation of the torque given the magnetic field, area, and the current

if myoo is equal to the NIA then torque equals myoo cross B.

magnets create a magnetic field and and the coils of wire carry current. The pole in the center is allowed to spin but not mov.

each time we changed the current, it spun the opposite way. When the magnetic field was flipped then the spin also changed. when both were changed the direction of the spin remained the same.

how we assumed the motor might degrade over time.

just the set up

a simple motor we created in class. The wire was coiled around a test tube and were tied to retain its shape. The insulating coating was stripped completely on one side and only half on the other side. This allowed the current not to flip, but for it to stop on half of the turn so the momentum could carry it forward.

determining equation for hall voltage

how gear speed is monitored in a car. The teeth of the gear change the magnetic field through the hall sensor, and the car can read the change in current. The waves tell the care how fast the gear is rotating.

equation for the relationship between the electric force and magnetic force in current carrying wires.

Today we had an introduction to magnets and how they are made up of a large FINITE quantity of tiny (magnets) called magnetic domains. When something is magnetic these domains are lined up. Magnetism is linked to electron spin however we did not get too much into that. We then saw how non-permanent magnets lost their charge and the professor demonstrated this phenomenon practically. We then looked at how current carrying wires can produce an electric field and how this is the basis for electric motors.