The first
thing we learned about in this unit was Newton’s Second Law of motion, which
states that acceleration is inversely proportional to mass and directly
proportional to force. Newton’s 2nd law written as an equation is
a=(fnet/mass). We then conducted a lab in which we tested Newton’s 2nd
law by using a rolling cart and a pulley system. After the lab, we then learned
about skydiving and falling through the air. I learned that when falling with
air resistance, F-air (force of air) is directly proportional to speed and
surface area. This means that if the speed or surface increases, then the f-air
will also increase. After falling for a certain amount of time, the skydiver
will reach a point called terminal velocity (constant velocity) where they
remain at a constant velocity. Next, we learned about free fall, which is falling
without air resistance. The force of gravity is the only force affecting
anything in free fall, where gravity is a constant 9.8m/s^2. In this case the
equation a=(f-net)/(mass) changes to a=g because the force of gravity on mass
is also known as weight. The equation to change weight to mass, and vice versa,
is w=mg. To find how high, d=1/2gt^2 is the right equation, while how fast
would be v=gt. Similar to free fall, we learned about throwing things straight
up as well. The acceleration acting on an object thrown up is always 10m/s^2,
and that drawing a picture of the path of the object is very helpful. The last
thing we learned about was falling and throwing things up at an angle. The most
important thing we learned was that the only thing that determines the time in
the air is the vertical height. An object falling at an angle will take a
parabolic path to the ground, and the horizontal force is always constant. When
an object is thrown at an angle at the top of it’s path, it still has a
horizontal force acting upon it.
The main
thing that I have found difficult in this unit is remembering all of the
different equations and what they correspond to. Especially since there are two
equations when solving for the vertical and another for the horizontal. I
overcame these difficulties by constant review and making sure I was correct
each time I solved a problem using one of the equations. I also found that some
of the equations are self explanatory, however some of them just require
memorization to what they correspond to.
I think
I’ve had a solid effort towards class, homework, activities, blog posts, etc. I
feel that this really helps in learning and understanding the material, because
the effort I put in helps in understanding the notes and other things during
class. My persistence is also a key factor in this class, because not giving up
is important when learning new material, even if it’s hard. Having
self-confidence in yourself is also important because if you’re not confident
than you might not ever ask a question that you don’t understand, which will
most likely lead to getting it wrong on the test. Lastly, collaborating with
your group members is important because you need to split the work up evenly,
and they can help you if you need it.
My goal for
next unit is to do even better on both open and closed note quizzes, because
they are relatively easy points if you study/go over your notes every night. I
plan to review my notes more, and also pay more attention when watching videos
and taking notes.
One
connection I can make is throwing things at an angle, because I often will
throw a football, Frisbee, or any other type of ball. It is interesting to
think about the acceleration and velocity the ball has when I throw it and when
it’s in the air.
