Physics of Driving

This weekend I drove out to a big deserted parking lot. I started at one end and accelerated to 20 miles an hour. When reaching 20 miles an hour, I let go of the gas pedal and expected for the car to go at constant velocity like we learn from Newton's laws in physics. But it didn't happen!! The car began to slow down the second I let go of the gas pedal!!
I thought that maybe it was an error in the slope of the road. So I tried again from the other side of the parking lot. But the exact same thing happened! That was when I remembered something from physics: there is the force of kinetic friction and air resistance acting upon the car, slowing it down and making Newton's laws seem flawed. It was a very insightful ride.

By the way, I was just kidding because I would NEVER disregard Newton's laws =)

Fun in the Elevators

This weekend, I taught my aunty the phenomenons of elevators. When the elevator door closed for the first time, and started up, I said "Our weight is exceeding the normal force." After my aunty gave a long and confusing stare, I explained that the equation for net force is mass times acceleration. Because our mass never changes, when the elevator accelerates, there is a net force. Accelerating up and decelerating on the way down, make you feel heavier because the force your weight imposes on the earth is greater than the normal force, or the force the elevator imposes onto you. When slowing down on the way up, or acceleration on the way down, you feel lighter because the normal force exceeds your weight, which is constant. I also explained that after the initial acceleration, the elevator moves at a constant velocity, with no acceleration, which is why in good elevators, it feels as if you aren't even moving.
I entertained my aunty by using my hands as vectors to illustrate the difference between the normal force and weight during our rides in the elevator. She was so amused that we rode it up and down three times before other people got on and gave us weird looks. Then, we figured that it was time to get off.

First Blog Entry

The first day of AP Physics was definately an interesting one.

I've never had a teacher outright ask why we would all tourture ourselves with AP Physics.
It made me scared for the upcoming year. But, I was excited to see what the first test would be like. I figured that if I kept up with reading, did my homework, studied for quizzes, paid attention in class, did my labs thouroughly, had discussions throughout the day with my lab partners, memorized my equations, went on class live and did all the extra credit, it would be all good. Ha, no big deal. Only twice the time I spend on any other classe.
But it's worth it. And it's fun.

I'm still really nervous about the AP exam. I have a feeling that I'm going to forget everything from quarters 1-3... and we haven't even started them. But from reading other people's blogs, I know a lot of other people are nervous about that too.

For now, I'm just going to enjoy physics!

Mad Physics

yayyyyy