Final answer:
The difference in the heights (h) in an open-end manometer does not measure the pressure in the flask directly but rather the difference between the gas pressure in the flask and the atmospheric pressure; thus the correct answer is b) False.
Step-by-step explanation:
Regarding the question of whether the difference in heights (h) in an open-end manometer is a direct measure of the pressure in the flask, the answer is: b) False. The correct interpretation is that the difference in height (h) indicates the difference between the pressure of the gas in the flask and the atmospheric pressure. If we take specific scenarios described in our references:
- For a positive gauge pressure (P₀), the height (h) of the fluid column is such that the pressure in the flask is atmospheric pressure plus hρg (P₀ = hρg).
- Conversely, if the gauge pressure is negative, the atmospheric pressure is greater than the gas pressure by the same amount (hρg).
It is important to note that the pressure of a gas in an open-end manometer is expressed as the atmospheric pressure plus or minus the pressure corresponding to the liquid column height (hρg), rather than simply h being a direct measure of the pressure.