The time an object first passes a point in simple harmonic motine

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The position of a mass in simple harmonic motion is described by the equation x=(0.078m)cos[2πt/(0.68s)]. The discussion revolves around determining when the mass first reaches the position x=-0.078m. The frequency of the oscillation is noted as 1.47 Hz. A participant initially struggled with the calculation but resolved the issue by switching their calculator from degrees to radians and using the inverse cosine function. Ultimately, the key variable to solve for in the context of this problem is time (t).
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1. The position of a mass oscillating on a spring is given by x=(.078m)cos[2∏t/(.68s)] when is the mass first at the position x=-.078m



x=A cos(2πt/T).



3. the frequency is 1.47. I really don't know were to go from here. can anyone help me?
 
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If you substitute x= -0.078 into the equation they gave to you, what variable can you solve for?
 
Never mind I solved the problem I just needed to change my calculator from degree to radiants
 
rock.freak667 said:
If you substitute x= -0.078 into the equation they gave to you, what variable can you solve for?

thanks but i just used the inverse cos.

(inverse cos(x/a)) / (2∏/2.4) = t
 
Once you understand why you were solving for 't' in the first place :)
 
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