Under standard conditions, surface atmospheric pressure is about how many pounds per square inch?

Under standard conditions, surface atmospheric pressure is about how many pounds per square inch?

• A. 29.92 psi
• B. 1.00 psi
• C. 14.69 psi
• D. 1013.25 psi

Answer: (C)

At sea level, the air pressure is defined as 1 atmosphere, which is about 101.3 kPa. When you convert that to pounds per square inch, it becomes roughly 14.7 psi. So 14.69 psi matches that standard value, making it the correct choice. The other numbers mix units or magnitudes: 29.92 refers to inches of mercury, not psi, and converts to about 14.7 psi, not 29.92; 1.00 psi is far below the ambient atmospheric pressure; and 1013.25 psi is far too large for surface air pressure.

At sea level, the air pressure is defined as 1 atmosphere, which is about 101.3 kPa. When you convert that to pounds per square inch, it becomes roughly 14.7 psi. So 14.69 psi matches that standard value, making it the correct choice. The other numbers mix units or magnitudes: 29.92 refers to inches of mercury, not psi, and converts to about 14.7 psi, not 29.92; 1.00 psi is far below the ambient atmospheric pressure; and 1013.25 psi is far too large for surface air pressure.