Answer :
Final answer:
The air pressure in an elevator accelerating upward is greater than the barometer reading of A) 76 cm as the upward acceleration increases the pressure inside the elevator.
Explanation:
The student asked about the air pressure reading in an elevator accelerating upwards. The barometer reading in an elevator accelerating upward is 76 cm. Since the elevator is accelerating upward, it creates a higher pressure inside due to the force exerted by the elevator's floor to accelerate objects upwards including the air inside the elevator. Thus, the correct answer to the question is that the air pressure in the accelerating elevator is greater than 76 cm of mercury (> 76 cm). This can be understood by comparing this scenario to one where a bathroom scale reads higher than the actual weight of a person when the elevator accelerates upward due to the increased force required to move upwards, as described in Example 6.3.
