Magnet

We started the day understanding about magnets. A paper clip does not have a magnetic charge. When it is given magnetic charge by being placed in a horseshoe magnet and cut into half, the magnetic charge is shown by using a compass. The compass moves when the paper clip is moved closer to it.

Understanding Magnetic Field:

Magnetic field is the magnetic vector space in which the forces movement around a magnet can be seen. The force moves from north to south pole of the magnet. Apparently, the drawing below by Adrian is falsely drawn and he didnt change it :( 

When you draw the magnetic field, it will follow the arrows drawn as before. This will look like a rainbow jumping from the north pole to the south pole of the magnet. 

This is a horseshoe magnet. It's just like a normal magnet, but the poles are bent to get closer to each other, so both north and south pole are on top.

We learn that flux is the number of poles enclosed. The formula for this is magnetic field times Area, which is also net nunber of poles enclosed per epsilon.

We also learn that the units known for magnetic field are tesla and gauss. Gauss is 

Understanding relationship between Force, magnetic field, velocity:

When we move a magnet towards a oscilloscope, the bright dot in oscilloscope move to a certain way. When the magnet is moved closer from the top of the oscilloscope with the north pole pointing downward, the dot moves to the left. This shows the direction of Force. Using right-hand rule, we can figure out the direction of velocity as shown on the first picture below. We can also predict the direction of Force and velocity when the south pole of magnet is brought close to the oscilloscope using the same method. We found the Force to move to the right and velocity is moving away from us. When north pole of magnet is moved closer on the sides of the oscilloscope, the force moves downward and moves upward when south pole is moved closer. Lastly, we try to move the magnet inward/outward, we found that there is no movement in the Force. Thus, we conclude that Force is zero when magnetic field is parallel to the beam. This right-hand rule only applies for protons, whereas electrons will use a left-hand rule.

We then learn that Force is a cross product of charge and velocity by the magnetic field. By deriving it, we can find the magnetic field units to be kg/Cs, or is also known as N/A.m

Given the value of magnetic field, velocity, charge, and angle. We can calculate the magnitude of force by using the formula that we just learned and found the force to be 6.24* 10^-16 N as below. We also We can then find the acceleration using the mass of the proton that we know ti be 6.67* 10^-22kg. Using the newton's second law, we found the acceleration to be 9.35* 10^10 m/s(square).

Understanding Magnetic Field in Charged Wire:

For our next eperiment, we will place a wire horizontally in between the horseshoe magnet. When the wire is given charged, the wire jumps up. This shows that 

We knew from phys 4A that radial force is mv(square)/r. We can set this equation equal to the equation force that we just learned. By deriving these equations, we can find r to be mv/q x B.

Velocity does not only move in a straight line, it can also move radically. The direction of velocity can still be found by using the right hand rule. This velocity is positive when moving in clockwise direction and negative when moving in counter clockwise direction.

We can find a magnetic field from a known frequency. Recall from phys 4A that omega is v/r, which we can use to replace velocity in the magnetic field equation from earlier. We found the magnetic field equation to be m*omega/charge. We also know that omega is 2*pi*frequency. Thus, we can calculate the omega, then plug it in to find the magnetic field.

Understanding Magnetic Field in Charged Coiled Wire

For our next eperiment, we will place a coiled wire horizontally in between the horseshoe magnet. When the wire is given charged, the wire jumps 90*. This shows that