Here's my pop quiz answer.

m*g*h = 1/2*m*v^2.....initially we have v1 = sqrt(2*g*h1) = sqrt(2*9.8m/s^2*1.50m) = -5.42m/s [Note the negative means it is going down]

The rebound velocity v2 = sqrt(2*g*h2) = sqrt(2*9.8*0.90) = 4.20m/s

a) For this initial v = 0 and final v = -5.42m/s...SO impulse = m*vf - 0 = 0.050kg*(-5.42m/s) = -0.271kg-m/s

b) Here initial v = 4.20m/s anf final = 0 .... so impulse = 0 - m*vi = -0.050kg*4.20m/s = -0.210kg-m/s

c) Now the impulse (which is the change in momentum) = m*v2 - m*v1 = m*(v2 - v1) =
0.050kg*(4.20 - (-5.42))m/s = 0.481N-s

I can't imagine anyone knocking this out before me. I didn't have a chance to check though. Time for a nap.
 
 
2010-1-24   the hardest teacher ever

I'm out of the infirmary and on crutches. I have nothing to do but homework. I wish I was on an adventure somewhere! Shirley has been pretty nice of late - she even made me a cake for my un-birthday!

X-1 told us on Friday we had to read 1000 pages of our text on fringe theories. I'm stuck on one exercise that asks me to consider the Lorentz transformation as invariant in a number of equations related to the passage of radiation through spacetime. I know X-1 just wants the students to get really into learning and I feel bad for him, but not using the Lorentz transformation in these exercises seems pointless so I'm just fudging some numbers so I can call it a day. I'm passing, so whatever.

I wonder if he would have more success if next Friday he made a quiz game for the class. He could ask us questions about how well one superstring theory or another explains...I dunno, fermions or something, and the trick answer would be about tachyons.

Ha! Tachyons.
 
 
2010-1-15

I am recuperating in the infirmary.

I found Widow's Peak but it is some kind of artificial mountain built by forest monsters. I never should have listened to that fairy guide, and I never ever should have entered the underground 'Hive Lair' the fairy said would be perfectly safe. I'm such an idiot. STUPID STUPID STUPID.

Now I'm behind on a week of schoolwork, I missed the Junior Mountaineers meeting on Wednesday, plus my girlfriend yelled at me for being dangerous. Augh, I gotta go, I can hear her outside. Here comes another lecture. Blah blah blah rules rules rules.
 
 
2010-1-11

My name is Parker and I love mountains!

Today in Parallel Universe Economics class, I heard someone whispering about how they were going to go climb Widow's Peak on the other side of the forest. I didn't know there were mountains by the school so I was really excited! But when I turned around to find who was talking...there was nobody there. Weird.

I think today after school I'm going to go hiking through the forest and find Widow's Peak!