Magentism

Get ready to have your mind blown- EARTH IS IN FACT A LARGE MAGNET.  How is this possible you may ask?  The answer is inside.  At the very core of our planet are lots and lots of metals that are moving charges.  With that being said, Earth then becomes the perfect magnet.  Your next question is probably now, "why isn't everything magnetic or sometimes magnetic?" Well, that answer lies in the domain of the atoms.  The domain is when the atoms are magnetically aligned, and thus able to create attraction between charges.  So, a paper becomes a magnet only when in contact with a magnet because some of the atoms are aligned.  That's magnetism for you!

Circular Motion and Forces in 2D

Big Questions:
1. What does it mean to analyze forces in 2D?
2. How do forces cause object to move in a circle?
3. What does it mean to be in orbit? How do satellites orbit planets? How do planets orbit the sun?

For this weeks lab, we engaged in tasks that would give us insight on motion is 2 dimensions.  This is different from analyzing a force in 1D because you only measure one variable, x or y.  But, with 2D there is two!  This will incorporate geometry and our best friend SOH CAH TOA. 

With the hover disk lab we spun a hover disk, with a string attached to it, in a circle.  The hover disk is ACCELERATING.  How you ask?  Not because its speed is changing, but rather because its direction is changing.  In order for an object to accelerate a NET force needs to be acting on it.  When we let it go it traveled in a 90 degree angle.  Again, why?  Because of Newton’s 1^st law.  To address the third big question, the tension force keeps an object going in a circle (which is identified as orbiting).  This is how planets orbit the sun.  They are in a sense falling toward the earth.  Due to speed however they miss their target and keep on accelerating.  

Projectile Motion

This week for our lab the class furthered our knowledge of physics by studying projectile motion.  What is a projectile?  An object in motion with only the force of gravity that is influencing it.

 

How does one analyze projectiles?  For our class we went down to the gym and shot some hoops.  In the gym, we took videos of ourselves shooting (this is very accurate because one has to remember that a projectile will travel with a parabolic trajectory). 

 With the Vernier App we were able to plot our points in time (x and y coordinates seperately) and graph position over time with the velocity over time graphs.

With all of this information we were able to derive these equations

y=mx+b
y=acceleration
m=slop=velocity
x=time

Real Life application:

The best shooter of all time, Miami Heat guard Ray Allen, is an exceptionally talented athlete as well as physicist.  Allen understands the concept of projectile motion as he has made the most three pointers in NBA history and has a career free throw shooting percentage of 89.4%