Monday, October 29, 2012

Dynamic Based Problem: Bouncing (Hypothesis)

So, two balls are next to each other, and both bounce the same height despite their different sizes.
Then if you position the balls a bit differently, with one on top of the other instead of next to the other, then the ball on top flies much higher than it would normally bounce. Because of this, the ball below bounces significantly less the distance than it would normally bounce.

My hypothesis to this horrible phenomenon is that the energy from the lower ball gets transferred to the ball on top of when the upper ball bounces against the lower ball.
If you think about it, it makes a bit of sense before you even experiment. If something at rest pushes an object, then will it go very far? Now compare that to an object in motion pushing another object. Yeah.

Before we get started, I'll my plan of action is to conduct this experiment several times and take notes. I may even look this up if I get desperate. Then, I shall connect this to Newton's second and third laws and use fancy words like mass, weight, and inertia.

The California Standards associated with this dynamic based problem are:


1. Newton's laws predict the motion of most objects. As a basis for understanding this concept:  

a. Students know how to solve problems that involve constant speed and average speed.  b. Students know that when forces are balanced, no acceleration occurs; thus an object continues to move at a constant speed or stays at rest (Newton's first law).  c. Students know how to apply the law F=ma to solve one-dimensional motion problems that involve constant forces (Newton's second law).  d. Students know that when one object exerts a force on a second object, the second object always exerts a force of equal magnitude and in the opposite direction (Newton's third law).  e. Students know the relationship between the universal law of gravitation and the effect of gravity on an object at the surface of Earth.  f. Students know applying a force to an object perpendicular to the direction of its motion causes the object to change direction but not speed (e.g., Earth's gravitational force causes a satellite in a circular orbit to change direction but not speed).  g. Students know circular motion requires the application of a constant force directed toward the center of the circle.  h. * Students know Newton's laws are not exact but provide very good approximations unless an object is moving close to the speed of light or is small enough that quantum effects are important.  i. * Students know how to solve two-dimensional trajectory problems.  j. * Students know how to resolve two-dimensional vectors into their components and calculate the magnitude and direction of a vector from its components.  k. * Students know how to solve two-dimensional problems involving balanced forces (statics).  



I wanted to add picture because I explained this horribly, but ran out of time...so oh well.

Monday, September 24, 2012

Free Fall Physics Video

This video is super amazing. It has some guy throwing axes in the background while some guy with an accent from strange foreign lands is explaining free fall. He has a pretty awesome drawing of his example, and the background looks pretty strange. I don't think this man is from Earth, but oh well. He explains free fall in an understandable manner.

His example is realistic and relates to real life. One can see how dropping a ball from a tree is an example of free fall, and how even a simple task like this can relate to physics. That's pretty cool.

I don't know how to say this, but somehow his explanations make sense. They just do. Even though he isn't a professional guy, he seems pretty knowledgable about the subject. He should have been hired for Science Channel for making this video.

Well, this was the most appealing free fall video to me. The other ones I found were just nerds talking about math for 5 minutes then dropping an object for 2 seconds of the video.

If I made a video, it would be exactly like this. Just kidding.
It would be similar to this, but I don't know if I could get a man throwing an axe in the background, and maybe I'd make it better quality. It would probably be more planned, and more technologically advanced (instead of using a whiteboard), and I'd make the dropped item more noticeable. Just for fun, I'd make a slow motion segment of the item falling because I can. And I'd provide plenty of educational value to the audience, with super fun examples and stuff like that.
And then one day I could be on Science Channel and make millions.

Saturday, September 1, 2012

Spaghetti Tower

Our building plan. Pretty fancy, right?

Overview:

Our total was $400 spent, but we had 4 spaghetti sticks left over. We bought 22 sticks (18 used), 8 cm of tape that we traded for marshmallows, then bought 10 cm of tape after. After some hard, strenuous work, we finally built our tower up to approximately 82 centimeters.

Design and group evaluation:

Our design, originally, was flawless. We had the perfect triangular tower and used some math to figure out exactly what we needed. So, we took our materials and got to work. Unfortunately, the tape wouldn't stick very well, so we achieved minimal progress on the first day.

For our second day, we met a new merchant, who decided to let us trade our tape for marshmallows. He took about 7 cm of tape from us (because we had tried to use 1 cm, which got spoiled), and in return gave 7 marshmallows. These were the perfect replacement for our tape, especially for the evil corners of the figure.
Final height and structure.

So, we tried stuff out. our base was going perfectly, and we followed the plans. We were on a roll, and didn't cut our spaghetti sticks, but instead slid them into the marshmallow far enough to seem like a shorter stick.
This is what we ended up with:

Yeah. Not our plan. We looked around, knowing that this base wouldn't be sufficient, and decided to redesign our building. We decided to make the spaghetti stick straight up and use our super solid base.

Well, we built it. The top started freaking out and falling over, so we purchased a lot more tape. This solved the problem, and our tower was invincible. Well, until we smashed it.
The most grand challenge we faced was trying to get the straight up pieces of spaghetti to stay up. Eventually, we bought more tape and taped them to other supports, making it sturdy and long lasting.
If we had the opportunity to redesign our tower, we'd probably make it more fancy. Maybe make it look like an hourglass or something, because, although the base of our tower was cool, our tower looked pretty bad.

Self Evaluation:

While doing this activity, I felt pretty confident. I've done this a bunch of times before, and tried to make it as sturdy as possible originally. During the activity, however, our tower turned out a little different than expected, so I redid the designs in an effort to save time and money.

Our design was really similar to others in the room after we modified it. It seems they tried to copy us, however, most of them couldn't replicate the delicate artwork involved in our tower. 

If I could add another material, it would be duck tape. I liked how the tape looked on our tower, but the painter tape wasn't sticky enough. Duck tape would be a pretty good fix because, of course, duck tape fixes everything.

Our group consisted of two people, so my contribution was large. I helped build the tower, bought some supplies, and calculated the original design. Both of us helped build, take pictures, and calculate the secondary design.