Middle School Physics: Adrift
Step 2: Analyze Data
Practice Analyzing CODAR Images

Now let's apply your knowledge of vectors to some real CODAR images.

In the following image, the CODAR system has produced a vector indicating the direction and speed of the surface current. The arrow you see is the combined, or resultant, motion for all the forces acting on the water at that point.

1. Click on the thumbnail below to enlarge the image, and examine the vectors. Continue with steps 2-4 below, and then close the window when you're done to proceed with the project.

2. Refer to the the "Adrift" Activity Worksheet to answers the questions under "Practice Analyzing CODAR Images".

3. Determine the current velocity (cm/sec) using the color scale on the right of the graph.

4. Use the COOLroom "Speed Conversion" calculator to convert the velocity to km/hour. To get there, scroll down to the middle of the COOLroom's Ocean Surface Currents from Coastal Radars page. Close the window when done.

5. Use the map scale (km) to determine the distance between the starting point (the non-arrowed end) of the vector and the point on land reached by drawing a straight line from the vector (in the direction it is pointing) until you hit land. Use the following formula to determine how long it would take for a wave starting at the vector to reach shore.

If you know that Distance = Rate (or velocity) x Time, you can rearrange the equation as:

Time = Distance/Rate (or velocity)

Be sure to record your answer on the Adrift Activity Worksheet.