24

this weekend, i caught a ride on teh bus to my track meet which was at kamehameha. while i was sitting down in the bus, i noticed couple things that were physics related stuff. for example, i noticed the usage of mirrors. there were mirrors arranged in a manner so that bus driver could see most of the things around him. another thing i noticed was the glass windows which acted like a mirror. while i took a glance at the reflected image on a window, i noticed that the image distance and object distance of the scenery were the same, which was pretty cool. also, i noticed that there were many convex mirrors so that people could see a lot of things around them. after learning how stuff works in physics, life became more fun, doc.

23

The "Mirage Mirror" is really two parabolic mirrors with identical shapes. One (mirror A (bottom)) lays face-up on the table while the other (mirror B (top)), which has a hole in its center, lays face-down on the first mirror. They are designed so that the focal point of one lies just at the vertex of the other when they are placed on top of one another. An object placed at the middle of the bottom mirror will be at the focal point of mirror on top. Light from the object reflects off of mirror B into parallel paths. This light shines on mirror A, reflects, and converges to the point fA. This light makes a real image at fA. If you look at this point, you'll see the object appear to hover at that point.

22

this weekend was very key doc. i had a track meet and wow, it was full of physics. take long jump for example, that thing is a great example for kinematic equations. a runner wants to get the greatest x velocity (speed youre running forward) and then get the maximum y acceleration/velocity (height). that's like projectile motion we learned except in the real life long jump there's wind speed, air resistance, what so ever. also, take a look at them spikes. whoever thought of using spikes must know a lot bout physics because they mustve known that more friction on your shoes makes you get the minimum energy loss through impact. another one is discuss throwing. instead of throwing it in a linear motion, they use rotational force because centripetal force and so on gives greater speed and energy to throw. the speed is the tangential speed which the discuss obtained through rotational dynamics. this is why i run track doc.