Question

1 sep plan an investigation what experiments would you do to learn more about how sailing stones move across the valley?
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2 sep define problems what variables can you identify that could be used to model a stone’s motion?
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3 ccc cause and effect what do you think might cause the stones to move across the valley?

Explanation:

Sub - Question 1: SEP Plan an Investigation

To learn about how sailing stones move, we can design experiments considering different environmental factors. For example, we can create a scaled - down model of the valley floor (using materials like sand or clay to mimic the terrain) and place stones of different sizes and shapes on it. Then, we can vary the wind speed (using a fan at different settings) and observe the movement of the stones. We can also introduce water (by spraying a fine mist or creating a small stream) to see how it affects the stone's movement. Another experiment could be to change the slope of the model valley and see how the stones move under the same wind and water conditions. By systematically varying these factors (terrain, wind, water, stone characteristics, slope), we can determine which factors are most influential in the movement of the sailing stones.

When modeling a stone's motion, we can identify several variables. The independent variables could include the wind speed (how fast the wind is blowing), the slope of the valley (the angle of inclination), the mass of the stone (how heavy the stone is), the surface texture of the valley floor (smooth, rough, sandy, etc.), and the presence or absence of water (moisture on the surface). The dependent variable would be the motion of the stone, which can be measured in terms of distance moved, speed of movement, direction of movement, and the path it takes (straight, curved, etc.). Also, environmental variables like temperature (which can affect the state of water, e.g., freezing or melting) and air humidity could potentially be considered as they might influence wind and water conditions.

There are several possible causes for the stones to move across the valley. Wind is a likely cause as it can exert a force on the stones, especially if the stones are light enough or the wind is strong. Water, in the form of melting ice or rain - created streams, can also move the stones by either carrying them (if the water flow is strong enough) or reducing the friction between the stone and the valley floor (by creating a thin layer of water, similar to how ice can make surfaces slippery). The slope of the valley can contribute as gravity can cause the stones to move downslope, especially when combined with wind or water forces. Thermal expansion and contraction of the stones or the valley floor materials could also cause small movements over time, and perhaps even seismic activity (though less likely for regular movement) could jostle the stones into motion.

Answer:

• Create a scaled - down valley model with different terrains (sand, clay). Place stones of various sizes/shapes on it.
• Vary wind speed (using a fan) and observe stone movement.
• Introduce water (mist/stream) and note its effect on stone movement.
• Alter the slope of the model valley and repeat the above steps.

Sub - Question 2: SEP Define Problems