Question

what do you observe when Ice cold water is filled in a glass tumbler

Answer 1

if you will fill ice cold water in a glass tumbler you will observe that the evaporated water in the environment is condensing on the glass tumbler

Answer 2

when the ice water is kept in a glass tumbler..the air near the surroundings get condensed and it leads to the formation of water vapours on the surface of glass tumbler..
Hope it is helpful..☺