The correct option (D) 1 + (7π/12)s
Explanation:
t3 = time to travel from D to C = {(Distance Dc)/(Velocity)} = (60/120)
= (1/2) sec.
t4 = time to travel from C to D = {(Distance DC)/(Velocity)} = {60/120}
= (1/2) sec
∴ Time to complete 1 oscillation = t3 + t4 + t1 + t2
= (1/2) + (1/2) + (π/3) + (π/4)
= 1 + (7π/12) sec