Hi,
I am having trouble arriving to the correct answer for the following question: the time elapsed is 40.0s, the amplitude is 30.0cm, and the frequency is 0.05Hz for the following wave (in the attached file). I need to find the phase constant and find the phase at 40.0s. I did: (A/2)=Acos(theta) because at t=0, wt=0. I rearranged for theta and got answers like 120deg, 60deg (pie/3 rads), but thats not correct-I might be f*cking up on some final part.? Any suggestions?

uh thats definitely phase shifted, you forgot the Phi term in cos (or whatever greek letter you decide to call phase shifts)

Originally Posted by kiol

Hi,
I am having trouble arriving to the correct answer for the following question: the time elapsed is 40.0s, the amplitude is 30.0cm, and the frequency is 0.05Hz for the following wave (in the attached file). I need to find the phase constant and find the phase at 40.0s. I did: (A/2)=Acos(theta) because at t=0, wt=0. I rearranged for theta and got answers like 120deg, 60deg (pie/3 rads), but thats not correct-I might be f*cking up on some final part.? Any suggestions?

Ask this question on Avenue--that's what it's there for.

looks like -2pi/3

u didnt put -A/2 in ur equation...