When doing the Torricelli experiment correctly, which of the following factors is the measurement result related to () A. Weather conditions B. Straightness of the glass tube C. Tilt of the glass tube

When doing the Torricelli experiment correctly, which of the following factors is the measurement result related to () A. Weather conditions B. Straightness of the glass tube C. Tilt of the glass tube. (1) The mercury in the glass tube is supported by the external atmospheric pressure. If the tube is vacuum, the pressure generated by the mercury column in the tube is equal to atmospheric pressure. Adding more mercury into the mercury tank, slightly tilting the glass tube, changing the glass tube with a larger inner diameter or the curvature of the glass tube will not affect the height of the mercury column.

(2) Weather changes will cause changes in atmospheric temperature. Everything has the property of expanding when heated and contracting when cooled. When the temperature changes, the volume will change, and the number of air molecules per unit volume will also change, so the weather changes will affect the atmospheric pressure.

So choose a.