week of April 29

this week we started learning about wave lengths. we learned that a compressed part of a slinky in a longitudinal wave  is called a compression, while the uncompressed part is called a rarefaction. the true definition of a longitudinal wave- energy transfers in the same or parallel direction that the object moves.while a  transverse wave- energy transfers perpendicular to object motion. we also learned some definitions. wave length- distance between two successive ( in a row) points on a wave

period- time for one cycle

frequency- how many full cycles happen per second 

amplitude- maximum displacement from the zero line ( equilibrium point) 

oscillation - cycling between two extreme points, usually opposites

wave interference. 1) constructive when the waves build up happens when the waves are going the same way 2) destructive where the waves cancel each other out. the speed of a wave is measured by the wavelength \ period.

wavelength / period= speed

period = 1/frequency

wavelength* frequency= speed

Speed= V

Wavelength= lambda

frequency= curly q 

Boat Reflection

1) three factors that could have caused the boat to sink, 1, the lack of support on the bottom. So if a person who weighs 100 pounds puts weight on the boat, it shouldn't just have 1 piece of cardboard trying to hold them up, its going to collapse. 2, the height of the boat, If the boat was to short, when they sat down its obviously going to go down a bit, and if its too short water will seep through. 3 You also need enough cardboard to support the "forsaking".
2) The ones that didn't sink, had supportive structure and enough tape for the water to not sink in.
3) The lowest center of mass is helpful because it allows people to know where to sit in the boat, and how they should stay.
4) our boat did a lot better than i thought it would. It stayed afloat, the only trouble we had was how to row. I was rowing too hard, compared to the other rower. and so it took us a while to get down and back.
5) best rowing technique would be not at the same time, and have each on one side, not switching.
6) if i had to do something different i would have worked on how to row, and practiced.

Week 21 Physics

This week in physics we started learning about the solar system! Not really, more of the gravitational affects the earth and sun have on each other. We learned that planets and moons orbit stars. The path that they have is called an elliptical path, with two focus points or foci's(shown in figure 1)  The force of the earth on the moon is equal to the force of the moon on the earth, because they are force pairs, and force pairs are equal but opposite  But! they might have the same amount of force, but there is a bigger effect on the moon, because of its mass. Also shown in the picture is if the planet wasn't affected by the sun's gravitational force, it would continue in its tangent path! We also learned that the earth is tilted which causes the different seasons in the hemispheres. This week, we learned that the moon does not orbit the earth, it looks like it does but it really doesn't, it orbits the sun, but because the earth's gravitational force is there, it get's pulled in, but not enough to continue to orbit the earth. This is shown in the second picture!

Week 15- Phyics

This week we had our mousetrap cars! I have to say this project was a little stressful, but I tried my best.
So basically, you had to make a car, out of a mouse trap, you had to use CD's as the wheels, and you could use string and balloons, basically anything except a rat trap. I made mine with 4 CD's, and the back CD's had a cut balloon around them for traction. Then there was a wooden dowel attached to the mouse trap with a string, that wrapped around the back axle, which was a pen, to make the car move when the trap was set off. The axle was attached with 4  hooks drilled in to the sides of the trap. and then the pens were placed in there. Your car had to go at least 3 meters, and you had to find out the acceleration. so you used the equation Xf= (1/2) a(t)^2 + Vf(t) + Xi.