the goal:

Determine the value of atmospheric pressure using a mercury barometer.

Materials and tools:

tube 90 cm - basin - mercury - glass plate - holder

Steps:

1) Fill the test tube and the glass bowl with mercury.

2) Drop the test tube in the pelvis and note what happens. 

Note:

The drop in the level of mercury to a certain extent is equal to 76 cm, which is the value of the atmospheric pressure at sea surface in normal conditions.

Conclusion:

The atmospheric pressure is 76 cmHg.

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