Tuesday, January 26, 2010

Circular Motion Reflection

What I learned about uniform circular motion is that it is the motion of an object in a circle with a constant speed. Even though the object has a constant speed that doesn't mean the object isn't accelerating. Because the object would be changing direction, it would have an acceleration as well. This acceleration is called the centripetal acceleration. Probably the most important thing I learned about circular motion is the centripetal force. This is the inward force that must be applied to an object to keep it moving in a circle. Before this unit, I would get off a roller coaster at Six Flags and say, "man, could you feel that centrifugal force?" Now I know better and have learned that the inward force keeping me in my seat was actually the centripetal force.

What I found most difficult about what I have studied was deciding which equation to use. Given that the variables in the three equations were so similar, I had a hard time making sure I was using the correct equation. But of course, with practice I improved at this and now know the differences with each equation. For instance, I should only use the equation v = 2(pi)r/T when I can figure out the period. Even though some parts of this unit were hard I tried my best to figure them out.

My problem solving skills after learning about circular motion have improved because I have learned how to deal with problems that I can't get at first. Some problems that I have come across involving circular motion to me seemed to be too difficult. However, once I challenged myself to take on these kinds of problems I sometimes got the correct answer which helped my problem solving skills by getting me used to harder problems.

Saturday, January 9, 2010

Fig Newton's Second Laws Questions

What I have learned about Newton's second law of motion is that the acceleration of an object is proportional to the net force. The equation that shows this is Sigma F = ma. The net force is in newtons. This is important because it shows the connection between the cause of an object moving which is the net force and the effect of an object moving which is the acceleration. This also creates friction in the system. I have learned how to apply this concept to things like an Atwoods machine as well and have widened my knowledge of how the acceleration of an object is related to that object's force.

What I have found most difficult about what we have studied is drawing the FBD's for the Newton's second law problems and figuring out how to make an FBD into an equation. This gets even harder when there are two or even three FBDs involved. Despite this, however, I have been able to get a grasp on how to figure out the equations from the FBDs and it hasn't been that much of a problem.

My problem solving skills have definitely improved because of this unit. Some strengths of my problem solving would probably be applying the techniques from simple problems to harder ones to help complete them. This strategy has helped me solve many problems that I thought I couldn't do. A weakness of my problem solving skills would probably be not figuring out how to use the FBD to make an equation. Finding the net force from the FBD can sometimes be very difficult for me. Even though I have my weaknesses with problem solving I believe that this unit has helped my problem solving skills.