Simple Harmonic Motion Phase angle

[Jimmy84]

Homework Statement

What is the initial phase angle of this graph that describes a simple harmonic motion?

Homework Equations

The Attempt at a Solution

I don't have any clue about how to find it by watching the graph, I know only an equation to find it. Any help please.

 

[PeterO]

Homework Statement

What is the phase angle of this graph that describes a simple harmonic motion?

Homework Equations

The Attempt at a Solution

I don't have any clue about how to find it by watching the graph, I know only an equation to find it. Any help please.

I did a quick google search for "phase angle of shm" and the first site offered gave a good lead ... equation 510.
Any of the other offereings may have been just as useful.
Many were to other questions about phase angle here on Physics Forums in fact.

 

[Jimmy84]

I did a quick google search for "phase angle of shm" and the first site offered gave a good lead ... equation 510.
Any of the other offereings may have been just as useful.
Many were to other questions about phase angle here on Physics Forums in fact.

Do you mean this http://farside.ph.utexas.edu/teaching/301/lectures/node138.html ? I already read them but i just started reading the theory about Simple Harmonic Motion yesterday and I am a bit lost with it so is there any way to find the angle just by inspection of the graph? I didnt understand much of the previous posts about the subject on the forum

 

[PeterO]

Do you mean this http://farside.ph.utexas.edu/teaching/301/lectures/node138.html ? I already read them but i just started reading the theory about Simple Harmonic Motion yesterday and I am a bit lost with it so is there any way to find the angle just by inspection of the graph? I didnt understand much of the previous posts about the subject on the forum

That's the one.

I was particularly taken by the sentence before equation :

"Finally, the phase angle phi determines the times at which the oscillation attains its maximum amplitude, x=a: in fact"

If the phase angle was zero, then maximum amplitude would be happening then - so the graph of displacement vs time must look like a Cosine gragh.

A phase angle will translate the graph. Your graph is certainly translated. can you see by how much?