At sea level, the atmospheric pressure isa. 76cm of Hg column b. 0.76 cm of Hg columnc. 76m of Hg column d. 76cm of water column

To determine the correct atmospheric pressure at sea level from the given options, we'll analyze the choices based on standard atmospheric pressure values.

1. Atmospheric Pressure at Sea Level

• Standard atmospheric pressure at sea level is approximately 101.3 kPa.
• This can also be expressed as the height of a mercury column, which is typically 76 cm (or 760 mm) of mercury (Hg).

2. Evaluate the Options

• a. 76 cm of Hg column: This option matches the standard atmospheric pressure measurement.
• b. 0.76 cm of Hg column: This is incorrect as it dramatically underestimates standard atmospheric pressure.
• c. 76 m of Hg column: This is incorrect as it greatly overestimates standard atmospheric pressure.
• d. 76 cm of water column: This is also incorrect, as the water column has a different density and would not represent the same pressure as 76 cm of Hg.

3. Conclusion

The only accurate representation of atmospheric pressure at sea level among the given options is 76 cm of Hg column.

Final Answer

a. 76 cm of Hg column