What is Muta Rotation?
Please explain with a few examples..

Mutarotation refers to the spontaneous change in the optical rotation of a freshly prepared solution of an optically active compound with time. All monosaccharides exhibit mutarotation in aqueous solutions. 

For example: The specific rotation of a freshly prepared solution of alpha-D-glucose gradually decreases from +112 to +52.7 while that of beta-D-glucose increases from +19 to +52.7 with time. This change in specific rotation of an optically active compound in solution with time, to an equilibrium value, is an example of mutarotation.