ShareSolar System - Keeping in Shape
Journal
Entry - Take out your science journal and
answer the following question(s) (use drawings as appropriate):
What
keeps our solar system in shape?
Materials:
- String - 1 meter long
- Four large metal washers
- Stopwatch, timer with seconds, or clock with second hand
- Student worksheet
Procedure:
- Tie two washers on the end of the string.
- Swing it overhead, securely holding one end.
- Count the number of revolutions it makes in ten seconds. Use the person's nose as a reference point. Record on your worksheet.
- Repeat Step 3. Average the two trials.
- Fold string in half and repeat Steps 3 and 4.
- Add two more washers on the string.
- Repeat Steps 3-5.
- Complete the remainder of the worksheet.
Student Worksheet
Name ____________________________________________
Prediction: Which combination of washers and string do you think will go the fastest?
Hypothesis: ____________________________________________
____________________________________________
| Data Table | |||
| Experiment | First Test | Second Test | Average |
| 50 cm., 2 washers | |||
| 100 cm., 2 washers | |||
| 50 cm., 4 washers | |||
| 100 cm., 4 washers | |||
| Your experiment: | |||
Analysis Questions:
- What did the size of the orbit do to the number of revolutions the washers made?
- Which of the planets take longer than the others to revolve around the sun?
- What effect does mass have on a planet’s revolution?
- What would happen if there was no gravity?
- What would happen if planets’ forward velocity were changed (e.g. slower, faster)?
- What did your experiment show?
Conclusion: Remember to restate your hypothesis, and the correctness of your hypothesis, and explain what you learned. Use the back of your worksheet.
