Account for the following-
1) Hot air balloons are used in sports and for meteorological observations.
2) Glycerine is more viscous than water.

Dear Student,

Please find below the solution to the asked query:

For meteorological observations balloons are filled with hot air as hot air in balloon makes the balloon rise in air. A hot air balloon rises in air because hot air is lighter than air at normal (relatively colder) temperature.  

Hope this information will clear your doubts about this topic .

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