Last updated on 17 April/98
Physics 208. Physics of Sports, KKY.
The MS empire has standardized some things that is very useful. The .avi format of digital video can be read by a standard program in the win95 package.
This is the media player. It has play, fast forward, fast return and single step. The latter is the most useful for our purpose of making some measurements. You can single step and mark the position of the object for each step on the screen using a water soluble marker. Since each step is 1/30 of a second, you have a (x,t) coordinate from which you can obtain:
To do this make a measurement with a ruler of the positions (x) and then put it in a table. [This could be in excel] to get:
| t | x | v | a | |
| 1 | 0 | 5 | ||
| 2 | 1/30 | 7 | ||
| 3 | 2/30 | 9 | ||
| 4 | 3/30 | 12 |
From this you can get v1 = (x2-x1)/(t2-t1) etc.
Tip: MS Excel or any of the spread sheet programmes are an excellent way to make these tables of x,t, v,a and to plot them as well . It's astonishingly easy!
To get to the media player from the desk top
Start....accessories....multimedia....media player.