Monday, September 1, 2014

Thank you Julie Bean, Motion Expert


Today in class we discussed Newton's First Law of Motion, inertia. Immediately, I thought back to learning about inertia in fifth grade. We often watched videos from the television show Science Court,  which I enjoyed. So when I was assigned the task of finding a resource that helped to explain Newton's First Law, I knew exactly what I would pick. The beginning of the episode sets up the characters and the plot, but aren't really essential parts to the lesson. Starting at minute 6:56, there are various basic explanations of why inertia works the way that it does. In the video, motion expert Julie Bean explains that objects in motion like to stay in motion and objects at rest like to stay at rest. Like the video we watched in class today, Julie Bean demonstrates how the trick of pulling a tablecloth out from underneath dishes is an example of inertia. She also mentions that the reason seatbelts are necessary in cars in due to inertia. While you are in a car, your body is moving just as fast as the car is. Therefore, if the car were to stop and you were not wearing a seatbelt, you would fly out of the windshield because the law states that your body will stay in motion. She also addresses friction. Another girl in the court room demonstrates how a skateboard only stops because of the friction between the board and floor as well as between the board and the air. Julie Bean explains how if the stenographer were to go into space with a toothbrush and simply let it go, the toothbrush would be suspended in space forever. However, were the stenographer to push the toothbrush it would float through space forever. Her examples relate back to the Science Court's original case of why a decorative ball on a wire attached to the back of a bicycle (called a baad) would hit someone on the back of their head when the bicycle stopped.


The examples in the Science Court video helped me understand the first example of inertia that we watched in class today. Ms. Lawrence pushed a cart containing a small ball down a track. When the cart passed a sensor on the track, the ball popped up and fell directly back into the cart. The video below shows a man demonstrating what Ms. Lawrence showed us in class today. Thanks to the explanations in class and the episode of Science Court that I watched, I understand that the ball fell back into the moving cart because it was still moving at the same speed as the cart, due to inertia.

Thursday, August 28, 2014

Physics 101 (by someone who hasn't taken physics yet)


I expect to have a greater understanding of the world around me at the completion of this Physics course. I hope that I learn why elevator pulleys work and how unscrewing the lid to my water bottle and riding my bike to get frozen yogurt relate to physics.

I think studying physics is important because it helps us understand how the world around us works the way that it does. Not only that, but when we have a better understanding of physics we will be able to use that knowledge to an advantage. Finally, studying physics is relevant in life because understanding laws of nature and being able to apply them to daily life can translate into other aspects of life. Learning how to solve problems based on applied knowledge is a good skill to have in life and acquiring that skill can be done through learning physics.

I think that problem solving is being able to assess an issue and find a resolution through applying previous knowledge.

One of my questions about physics is how I can see physics around me beyond just looking at simple machines. I also want to know more about Sir Isaac Newton’s discovery of gravity. I would like to know why there is no gravity in space and whether or not that means that the laws of physics are not applicable in space.

A goal that I have for physics this year is to answer the questions I have at the beginning of the course. I would also like to become better at problem solving. Finally, I want to create a successful mousetrap car.