Color and depth of water
The materials required for the experiment:
- A boat and life jackets
- 1 set of scuba diving gear
- An experienced scuba diver
- 1 high resolution underwater camera with flash
- 1 underwater handheld flood light
- 1 depth gauge
- Colored metal balls – red, yellow, green and blue
- A black marker pen
1. For this experiment, the independent variable is the color of the ball (i.e. red, yellow, green and blue) and the depths at which the observations are made – 5 meters, 10 meters, 15 meters and 20 meters. The dependent variable is the perceived color of the ball at different depths. This is determined by taking a photo of the balls at different depths. The constants (control variables) are the clarity of the water, whether fresh water or seawater is used, the time of the day and the weather.
2. The services of an experienced scuba diver are required, for this science project. Arrangements are made with the diver to rent a boat and the required diving gear. Select a diving location that has a depth of over 20 meters.
3. On the day of the experiment, a trip to the chosen diving location is made with the diver. Using the black marker pen, the colors of the metal balls are written on its surface. The diver is instructed to take photographs of the metal balls using the underwater camera at depths of 5 meters, 10 meters, 15 meters and 20 meters. He should also make a mental note of what he sees at each depth.
4. The photos are developed and the colors of the balls at different depths are determined. The results as to whether the colors are still visible at various depths are recorded in the table given below.
Be extremely careful to ensure the safety of all participants. Life jackets must be worn at all times, and adult involvement is mandatory. The involvement of a qualified and experienced scuba diver is absolutely necessary.