When I measure pressure in relation to depth, I found that as the depth increases, so does the pressure. I experimented this in a LARGE graduated cylinder. What would be the difference if I used a SMALL graduated cylinder versus a large one? What is the evidence for this? And what is happening on a molecular level to the molecules in the smaller graduated cylinder?
When measuring pressure in relation to depth, the size of the graduated cylinder can potentially affect the observations. Here's how:
1. Difference between a small and large graduated cylinder:
- In a small graduated cylinder, the column of liquid exposed to the atmospheric pressure is smaller compared to a large graduated cylinder.
- In a large graduated cylinder, the column of liquid exposed to the atmospheric pressure is larger.
- Consequently, a small graduated cylinder may have a smaller pressure difference between the upper and lower portions compared to a large graduated cylinder for the same depth.
2. Evidence for this:
- To observe a difference, you would need to use different depths in both cylinders and measure the pressure using a pressure gauge, manometer, or similar device.
- By comparing the pressure readings for the same depths in both cylinders, you should notice a disparity.
- The smaller graduated cylinder will likely exhibit a lesser pressure increase with increased depth than the larger one.
3. Molecular level explanation for the smaller graduated cylinder:
- Pressure is caused by the collision of gas or liquid molecules with the walls of their container.
- In a smaller graduated cylinder, there is less space for the molecules to move, resulting in a higher frequency of molecular collisions with the walls.
- As a result, even though the column of liquid in the smaller cylinder is shorter, there is a greater concentration of molecular collisions per unit area, leading to a higher pressure at any given depth.
Overall, the difference between using a small and large graduated cylinder lies in the amount of pressure increase observed with increasing depth. This difference is a consequence of the more confined molecular movement and collisions in the smaller graduated cylinder, leading to an amplification of pressure compared to a larger cylinder.