Physics - Equations of Motion: Vertical Motion

OPENING QUESTION: Imagine leaning out the window of the tallest building in the world, the Burj Khalifa -- oh let's say about 2001 feet up in the air. You (of course! have a supply of frozen grapes and your trusty wrist-rocket sling shot.

You launch a grape directly downward at 24.6 m/s.

    1. How long does it take to reach the ground?
    2. How fast is it going when it gets there?
    3. For double-extra bragging points here's a tough one, how far has it gone when its velocity has reached 129.9 m/s?
    4. Oh and just to make things more interesting, how long does it take to get to that point?

LEARNING OBJECTIVES:

  • Formative Quiz - how are we doing?

CALENDAR:

WORDS O' THE DAY:

FORMULAE OBJECTUS:

    • a = (vf - vi)/(tf - ti) (definition of *average* acceleration)

    • g = 9.81 m/s2 (acceleration an object experience on Earth) ONLY present in vertical motion (Y axis) problems

      0) vt=x (we won't EVER use this for vertical motion--- why not?)

      0) vt=x (this ONLY works in horizontal <x> motion!)

      1) vf = vi +at (Derived on Tuesday)

      2) vavg = (vi + vf)/2 (this is kinda obvious, and kinda useless)

      3*) xf = xi + vit + 1/2at2

      4*) vf2 - vi2 = 2a∆x

*substitute y for x for vertical problems

WORK O' THE DAY:

If you have finished all the parts of the opener, please work on rewriting ONLY your methods section of your lab to include the appropriate detail we discussed on Tuesday.

 

I'm up doing physics stuff at the district office today, See ya'all tomorrow