An object in SHM oscillates with a period of 4.0 s and an amplitude of 10 cm. How long does the object to move from x = 0.0 cm to x = 6.0 cm?
x(t) = Acos(ωt +φ )
The Attempt at a Solution
ω = π/2
Acosφ = 0 ⇒φ = ±π/2
Since object is moving to the right choose φ = -π/2
x(t) = Acos(ωt-π/2)
My question is how why does Acos(ωt-π/2) = =Asinωt