Three S.H.M's of equal amplitude A and equal time period in the same direction combine. The difference in phase between each pair is 60∘ ahead of the other. The amplitude of the resultant oscillation is :
2a
Resultant of first two with phase difference, (ϕ=60∘) will be R1=√3a with 90∘ diffrence in phase with the third. The resultant of third and
R1 is
R=√(√3a)2+a2=2a