Questioning the atmospheric pressure experiments such as the Madsenburg hemisphere and syringe pumping: it always seems to be a kind of pumping force of the vacuum, the

P1*V1=P2*V2

Or: P1/P2=V2/V1

Because of the very small change in V2/V1, the pressure inside the tube is small, and naturally, it's very easy to do the action of pumping out the syringe

Madsenburg hemisphere, if it is not vacuumed, it should be very easy to pull it apart.

If according to your modified program, it can be understood that the syringe is placed horizontally, then it is impossible to pull out, because VI is about 0, P1 is 1 atmospheric pressure, V2 is set to be the volume of the syringe, such as the syringe Pulled out, then the vacuum is much less than -0.1MPA, so it is impossible to pull out