
Initial phase 2π+3π=65π.
Also it can be seen as below

The initial phase angle ϕ0=π−6π
=65π
JEE Main 2021 — Physics Waves & Oscillations
Y=Asin(ωt+ϕ0) is the time-displacement equation of a SHM. At t=0 the displacement of the particle is Y=2A and it is moving along negative x-direction. Then the initial phase angle ϕ0 will be:
Held on 25 Feb 2021 · Verified 6 Jul 2026.
32π
6π
65π
3π
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