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kgal
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Homework Statement
A guitar string vibrates at a frequency of 440 Hz. A point at its center moves in SHM with an amplitude of 3.0 mm and a phase angle of zero.
a. Write an equation for the position of the center of the string as a function of time.
b. What are maximum values of the magnitude of the velocity and the acceleration of the center of the string?
c. The derivative of the acceleration with respect to time is a quantity called jerk. Write an equation for the jerk of the center of the string as a function of time and find the maximum value of the magnitude of the jerk.
Homework Equations
x(t) = Acos(ωt + ρ)
ω = 2∏f = v/r
The Attempt at a Solution
a. I found that x(t) = Acos(ωt + ρ) = Acos(ωt).
b. d/dt x(t)= dx/dt = v(t) = -Aωsint(ωt) = 0
dv/dt = a(t) = Aω^2cos(ωt) = 0
I know that you need to set the equations equal to zero in order to find maximum magnitudes but I'm stuck from there on.
c. da/dt = jerk = -Aω^3sin(ωt) = 0.
same problem for me as in section b where I had trouble understanding how I find the max. jerk.