Question

Why do we see water droplets on the outer surface of a glass containing ice-cold water?

Answer 1

Air contains water molecules in the form of water vapour. When the molecules of water in air during their motion,strike the surface if glass surface is cooler than the molecules of air they lose their kinetic energy lowering the temperature and get converted into droplets. They become slower when they collide, and they stick. This is condensation, which is why the surface of glass is wet. The water droplets condense on the surface of the glass known as dew.( condensation : the process of converting of water vapour into liquid. It is a warming process.)

Answer 2

when we take a cold water on glass we observe that some water  droplets are in outer surface of glass because of air contain moisture when the outer surface of cold glass contacts with the moisture  it become into water droplets