What is the angle of friction between two surfaces in contact , if coefficient of friction is `1//sqrt(3)` ?

What is the angle of friction between two surfaces in contact if the coefficient of friction is (1)/sqrt(3)

Answer the question briefly and the point: What is the angle of friction between two surfaces in contact having coefficient of friction (1)/(sqrt3) ?

The angle of friction betwen two surfaces is 30^@ ,what is coefficient of friction?

Static friction between two surfaces

Static friction between two surfaces

The angle of friction between two surfaces is 37^(@) . If cos37^(@)=4/5 ,coefficient of static friction between those two surface is ?