Take a glass vessel and pour some glycerine into it and then power water upto the brim. Take a quartz glass rod. Keep it in the vessel. Observe the glass rod from the sides of the glass vessel.

• What changes do you notice?

• What could be the reasons for these changes? (AS2)

When the glass rod is put in liquid than the part of the glass rod that is in glycerin will disappear as shown in figure below.

This happens because both glass rod and glycerin has almost same refractive index ( 1.47 and 1.5 ). Thus when the refractive index is same the speed of light is same in both the medium thus no bending of light takes place. Hence no refraction takes place and the glass rod disappears.