formulas

Thought it would be really useful if we put down the formulas and how the hell we use them because I know I have no clue where to use these damn letters...

Sincerely,

 Longboardlarry //Velocity as a function of time:// //v// = //vo// + //at// //Displacement as a function of time:// //x// − // xo // = // at // + // vo t // // OR // // x // = x//o//  + //vt + .5// //at//

Tasha a good beginning equation is: X=Xo + VoT + 1/2AT² where X = final position, Xo = initial position, Vo = Initial velocity, T = time, and A = acceleration.

"suicidal Bob decides to throw himself off the top of a 100m. cliff. If he runs off at a velocity of 10 m/s how far from the base of the cliff will he land?
 * Example problem:**

Orthogonality says that we can split up bob's fall into his motion horizontally (the x direction) and vertically (the y direction). Because we know the distance he goes down, and also know the acceleration due to gravity, we will solve the y direction first.
 * Solution:**

Y=Yo + VoT + 1/2AT² -100m=0m + 0m/s + 1/2(10m/s/s)T² (the 100m is negative, and the 10m/s/s is positive because he is falling, not going up)

20s²=T² Take the square root of that and you get: 4.4 = T

Now, obviously, it takes bob the same amount of time to fall the 100m as it does for him to travel horizontally to his final position. This saves a lot of time and angst because you can (instead of putting that time into the equation we used earlier) just do this: 4.4s x 10m/s (his horizontal velocity) = 44m

YAY! Now we know that the distance that bob fell was **44m.** from the base of the cliff. This should greatly help his family find his body. The End

-Drew (i made the picture too)

**Inertia** In simple terms, Inertia is the property of a body at rest to stay at rest, or in motion to remain in motion. Expression = __Wk__² =IG is known as mass moment of Inertia and is given in ft. lb. sec². G Often, expression Wk² = I in lb. ft² is used as "moment of inertia in weight units”. It is proportional to IG and its proportionality factor G = 32.2 is often lumped with other constants. -Precious

i'm going to add the problem that we went over in class today (the one with the three balls and the inclines) here when i can get to it -drew