Homemade barometer
Channel: MEL Chemistry
Date: 2020-02-19

How can you make a simple barometer?

Equipment: glass, balloon, scissors, wooden stick, needle, box cutter, paper, double-sided tape.

Cut off the balloon's tail and put the other half over a glass. Use a rubber band to fix it in place. Then, use double-sided tape to attach a wooden stick with a needle to the membrane. This will serve as the device’s indicator arrow. Set a sheet of paper next to the device and note the current pressure. Over time, the arrow will change positions: down as the pressure decreases, up as it increases. It is important to place the barometer in a place with a relatively constant temperature.

A barometer is a device that measures atmospheric pressure, which can affect the weather. Since our membrane is made of latex, it is very sensitive to changes in the pressure of its environment. If the pressure rises, the membrane bends down, and the arrow rises. With a decrease in pressure, everything is exactly the opposite. Observe the barometer for a week and mark the results on a paper – this will make it easy to see the relative changes in pressure. If you find out the normal pressure for your area, you can even predict the weather somewhat: higher-than-normal pressure is often accompanied by fair weather, and lower-than-normal usually means more cloudy.

Cool experiments are waiting for you in the MEL Science subscription!

Warning! Only under adult supervision