For particle P revolving round the centre O with radius of circular path r and angular velocity ω, as shown in below figure, the projection of OP on the x-axis at time t is
(A)x(t)=rcos(ωt+6π)✓ Correct
(B)x(t)=rcos(ωt)
(C)x(t)=rsin(ωt+6π)
(D)x(t)=rcos(ωt−6πω)
Answer: (A)
Solution
From the diagram, the particle starts at an initial angle of 30∘=6π radians from the positive x-axis. As it revolves with angular velocity ω, the angle at time t is ωt+6π. The x-projection is given by x(t)=rcos(ωt+6π).
JEE Main · 2023 · 08 Apr 2023 · Shift 2 · Single correct option