Sorry guys but there was an error in the last spread sheet for the rocket lab. Here is a revised copy. The data is faulty and our assumption about a being constant during the burn is also faulty. The rocket acclerates more at first so it actually reaches close to vf soon after launch.This means that vf is closer to vavg. However, that's one thing a lab does. It let's us know where our assumptions are out line. Using ttop - tbo gives a height based on vbo. The column other gives a height based on vbo squared. Thus the discrepancy between the two Htop- hbo columns shows our vbos are probably too high.This explains our impulses and heights being higher than expected.
My best guess about the data is that for the first run someone forgot that hbo was measured from 2 m from the pole so hbo is the cm sighted on the meter stick x 30 (/ 100 to get m) not x60 . Lets say that the first hbo is thus 1/2 as great. Lets see what happens when we divide this hbo by 2. see row 17 on the spreadsheet. We get poor, but not incredibly bad, agreement. Other possibility is that hbo was confused with htop. In any case here its ( well soon, still can't upload from here). I will post it as tonight's homework on Off course.
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