Two particles are executing simple harmonic motion at an instant of time 't' their displacements are y1=acos(wt) and y2=asin(wt) . Then the phase difference between y1 and y2 is
120∘
90∘
180∘
Zero
displacement of 1st particle=y1=acos(wt)=asinwt+π/2 displacement of 2nd particle=y2=asin(wt) phase difference between above two equations =Δφ=wt+π/2-wt=π/2=900 Δφ=90∘