Question

prove angle of friction is equal to angle of riposed ?

Answer 1

tan a=fL/N=u. sN/N =u.s - - - - - angle of friction

fL=u. sN

N=mgcosb

fL=mgsinb

So, tan b=fL/N=u. sN/N =u. s

So angle of friction is equal to angle of repose

Actually, I don't know how to attach an image so I can't show you the diagram