Magdeburg hemispheres

1. Content:

The exhibition items have three different sized hemispheres, each corresponding to an operation button, and there is a pressure gauge next to the button. Participants operate the button to start the air pump to extract air from the inside of the hemisphere, then hold the handle on the hemisphere and pull it hard. It is found that it is quite laborious, which indicates the existence of atmospheric pressure. The air inside the two hemispheres is pumped away by the air pump, reducing the number of air particles inside the sphere. The atmosphere outside the sphere will tightly press the two hemispheres together, making it difficult to separate. The more air is pumped out from the hemisphere, the greater the external pressure, and the more difficult it is for the two hemispheres to separate.

2. Principle:

The pressure exerted by the atmosphere on objects immersed in it is called atmospheric pressure, abbreviated as atmospheric pressure or barometric pressure. In 1654, Grick conducted the famous Marburg Hemisphere Experiment in Marburg, Germany, which effectively proved the existence of atmospheric pressure and gave people a profound understanding of atmospheric pressure.

The Marburg Hemisphere experiment proves that atmospheric pressure is very strong. Atmospheric pressure does exist. In the experiment, the air in both hemispheres was extracted to reduce the number of air particles inside the spheres. The atmosphere outside the sphere tightly compresses the two hemispheres together, making it difficult to separate. The more you withdraw, the greater the pressure.

3. Purpose:

The exhibition items set up a simple experimental setup to simulate the famous Marburg Hemisphere experiment, allowing participants to understand the basic concept of negative pressure and further comprehend the existence of atmospheric pressure.