Answer :
Final answer:
If the elevator accelerates upwards, the barometer reading will be more than 76 cm, indicating an increase in pressure due to the upward acceleration of the elevator.
Explanation:
When the barometer is kept in a stationary elevator and reads 76 cm, it measures the atmospheric pressure at that point. If the elevator starts accelerating upwards, the pressure at the bottom of the elevator will increase because the air molecules are being forced down by the floor of the elevator as it moves upwards. Therefore, the reading on the barometer will be more than 76 cm, representing higher pressure at the bottom of the elevator due to the upward acceleration.
