Weighing Air
Item
Title
Weighing Air
Is Part Of
Physics
See all items with this value
Description
An example from demonline (UCT Physics Department’s website with descriptions of educational demonstrations). Its descriptions reads: "A spherical flask of about 1 litre is suspended from one arm of a crude chemical balance. It is counterpoised by weights in the other pan, the tap attached to the sphere being open. This gives (roughly) the true weight of the glass. Unhook the sphere from the stirrup, attach the rubber tube from a rotary vacuum pump to the glass tube and evacuate for around 30s. Close tap, and re-attach stirrup. There will now be an upthrust on the flask equal to the weight of air removed, and the weights in the other pan will have to be reduced by about 1.2 g to restore the balance. Open the tap again: the air can be heard rushing into the flask (class must keep quiet), and the flask suddenly descends again".
Creator
Demonline
See all items with this value
Source
UCT Demonline
Resonances
experiment
See all items with this value
physics
See all items with this value
educate
See all items with this value
instrument
See all items with this value
laboratory
See all items with this value
balance
See all items with this value
listening
See all items with this value
medicine chest
See all items with this value
student
See all items with this value
curricula
See all items with this value
Type
Jpeg
