Homemade barometer

Safe­ty pre­cau­tions

Warn­ing! Only un­der adult su­per­vi­sion.

Equip­ment:

• glass;
• bal­loon;
• scis­sors;
• wood­en stick;
• nee­dle;
• box cut­ter;
• pa­per;
• dou­ble-sid­ed tape.

Step-by-step in­struc­tions

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.

Process de­scrip­tion

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!