This science project of a student at Texas School for the Blind and Visually Impaired examines how different surfaces affect waves.
Question
How do different surfaces reflect waves?
Hypothesis
The waves hitting the board will last longer.
Materials
- stream tray – (We used a tub from Wal-Mart that was long and thin)
- sand
- stones
- wood to fit the tray
- a source of water
- a braille ruler
Preparation
Rather than use a stream tray, a tub from Wal-Mart proved to be a more affordable option and was about the correct size.
Procedure
- Fill the tub to a depth of 4 cm.
- Place a board (on a slight angle) at the end of the tub.
- Create a wave that will be reflected off the board and count how many times the wave moves back and forth across the tank before it disappears.
- Replace the reflecting board with stones. Place a pile of stones at one end of the tray. These stones should be piled up to a level just below the top of the tray. Ensure that there is a seaward slope with the pile of stones and it is even across the width of the tank.
- Create a wave that will be reflected off the stones and count how long the wave moves back and forth across the tank before it disappears.
- Repeat using sand.
- Record your results.
Data:
- Rocks – Waves lasted for 13 seconds
- Board – Waves lasted for 15 seconds
Conclusion:
My hypothesis was correct. The waves that bounced off the board lasted longer.
NGSS Standards:
- Plan and conduct an investigation individually and collaboratively to produce data to serve as the basis for evidence, and in the design: decide on types, how much, and accuracy of data needed to produce reliable measurements and consider limitations on the precision of the data (e.g., number of trials, cost, risk, time), and refine the design accordingly. (HS-ESS2-5)
By Laura Hospitál
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