4. Quality of observations/data |
|
- Consistent data |
Increase m --> observe increase in X |
- Accurate measurements/ observations |
Measurements of m and X within g and mm accuracy
of instruments used. |
- Completed data table |
Elongation data for all masses recorded in
table and force calculated for all masses (at least five). |
- Correct units |
m (kg), F (N), X (m) |
- Qualitative description |
* |
5. Graph |
|
- Curve is appropriate to data trend |
Straight line (best fit) |
- Points plotted accurately |
Points correspond to data values in the table |
- Appropriate scale |
Scales can accommodate range of Force vs Stretch |
- Axes labelled with variables |
Force in newtons, stretch in meters. |
- Variables placed on correct axes |
Force on x axis; Stretch (X) on y axis. |
6. Calculations |
|
- Calculated accurately |
Calculated accurately with appropriate use
of significant figures. |
- Substituted correctly into relationship |
Data for graph inserted into ratio: delta
F/ delta S |
- Relationship stated or implied |
Slope is the ratio of force over stretch |
- Units used correctly |
Force (N), Stretch (m), slope (N/m) |
- Use all data available |
For slope calculation, the chosen points should
be ON the straight line, far from each other. |
7. Conclusion |
|
- Consistent with scientific principle |
Correctly and clearly matches scientific principle |
- Sources of error |
* |
- Consistent with data |
Conclusion/answer to question is consistent
with student's experimental data. |
- Relationship among variables stated |
** |
- Variables stated in conclusion |
Force and displacement (or their symbols)
are used in answer. |