Answer |
Units |
Points |
Marked |
|
trial four |
Variable |
kg |
2 |
ans + unit |
1. What is your mass in kilograms? |
time/s |
distance/m |
Variable |
m |
2 |
ans + unit |
2. What is your height in meters? |
0.00 |
0.00 |
Variable |
kg/m² |
2 |
calc + unit |
3. Find BMI |
0.88 |
10.00 |
230 |
Cm³ |
3 |
calc + unit + sigdigs |
4. Volume for 9.6 cm long by 3.9 cm thick by 6.1 cm |
1.49 |
15.00 |
Speed or velocity |
|
1 |
|
5. What is the physical meaning of the slope |
1.95 |
20.00 |
86.8 |
m/s |
3 |
calc + unit + sigdigs |
6. predict the distance the ball would roll after ten seconds. |
3.65 |
25.00 |
1.01 |
s |
3 |
calc + unit + sigdigs |
7. A ball falls 500 cm. Given that gravity = 980 cm/s², how long |
5.10 |
30.00 |
Variable |
|
1 |
dependent on 9 |
8. Will the ball obey your predictions above? |
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Variable |
|
1 |
|
9. Why, or why not, will the ball above obey your prediction? |
slope |
5.47 |
For use in war... |
|
1 |
military applications |
10.Why was the shape formed by a ball arcing through the air |
intercept |
4.75 |
parabola |
|
1 |
parabola |
11. What is the name of the shape of the curve |
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Notes: |
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#3: The intent was to see if you could use esisting data to obtain a derived result for a new formula, a common occurrence in science |
#6: Fifteen seconds is ambiguous as to the number of significant digits. 87 m/s would also be a fine answer. |
#7: will not be less than one: 2*500/980 = 1000/980 > 1. Square root results do not "cross" one. If your result was less than one |
then you "inverted" something. If your answer was 1.02 then you forgot to take the square root. |
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#8: Confused some students. Some chose to focus on #6 where repeating a ball speed seems difficult while others focused on #7 |
where repeating a drop is straightforward and easily done. Bear in mind that if we could design a machine to fire the tennis balls, |
then we really could repeat a throw speed. Then the tennis ball would be far more predictable, no? |
Maybe a motor spinning a couple tricycle wheels... |
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#9 Uncertainty does not mean unpredictability. You will always be uncertain of the exact amount of time each trip to the college will take, |
but you are usually certain that you will get there eventually. Amid uncertainty, predictability. This is another truism in science. So do not |
take uncertainty to mean unpredictability. It just limits our ability to make an exact prediction. If data forms lines or curves on graphs, |
then there is a pattern. And if there a pattern, then predictions can be made. Patterns mean that there a mathematical relationship |
underneath the system, a math relationship that can provide predictions. And, as always, some uncertainty in that prediction. |
And, again, in #6, just because we cannot throw a ball twice at the same speed is not a reason to dispute predictability: that is a human |
limitation. If we could throw it identically, then we would expect similar time and distance numbers. Witness the ball drop from 500 cm: |
1.02, 1.03, 1.04, 1.05, 1.05, 1.18 seconds. And doesn't that last number look suspicious? Yes – because we expect predictability. |