Measuring Barometric Pressure and Altitude

PocketLab Voyager, Weather, and Air can all measure air pressure. Learn about barometric pressure and how it is measured here.

What is barometric pressure?

Put your PocketLab in a bag, fill it with air, and seal the bag. When
you squeeze the bag, watch the pressure change.

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What is happening? When you squeeze the bag, the air molecules are being pushed closer and closer together and more are pushed back against the surface of the bag. You can feel the increase in pressure on your hand.

How does the sensor measure altitude?

There is more air pressure at lower altitudes due to gravity pulling the air molecules down. Your PocketLab can measure these small changes in air pressure and determine the change in altitude as well. 

How does the sensor work?

The sensor inside your PocketLab works on a similar principle. There is a sealed cavity that compresses and expands with the air around it, and a piezoresistor measures the tiny changes in the size of the cavity.

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