Objective
To observe and analyze horizontal water movement using drifters.
Materials
- Access to water
- Method of marking off given distance (e.g. on land, pier, or boat)
- Bottle drifters with string attached (e.g. Pop bottle filled with sand so that the bottle floats just below the surface of the water); oranges
- Timing device
- Student Worksheet
Procedure
1. Measure a known distance along a stationary location (e.g. shoreline, anchored boat). Select a starting point and mark it as point A. Measure a known distance along a parallel axis to the water to point B (should be at least 15 meters). Record distance.
2. Drop bottle drifter with attached string or orange in the water at Point A.
3. Use timing device to record time it takes for the bottle/orange to move to point B.
4. Use the data table below or on the Student Worksheet to determine the speed of the current.
Data Table
Latitude | Longitude | Time Interval | Distance | Speed | Direction |
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Student Worksheet