6. A mass suspended on a spring will exhibit sinusoidal motion when it moves. If the mass on a spring is 85 cm off the ground at its highest position and 41 cm off the ground at its lowest position and takes 3.0 s to go from the top to the bottom and back again, determine an equation to model the data.

Question

6.	A mass suspended on a spring will exhibit sinusoidal motion when it moves. If the mass on a spring is 85 cm off the ground at its highest position and 41 cm off the ground at its lowest position and takes 3.0 s to go from the top to the bottom and back again, determine an equation to model the data.

amistre64 · Answer

dampened or undampned?

anonymous · Answer

undampened

amistre64 · Answer

the middle of top and bottom is our "y intercept"

have the range of top to bottom is our amplitude

do we pull it or push it to get it started?

amistre64 · Answer

im thinking in sines; this thing starts in cosine tho

amistre64 · Answer

r = 85-41

y = r/2 cos() + n

anonymous · Answer

amplitude=85-41 divided by 2=22 

period=3sec 

y=22sin(2pi*t/3)

anonymous · Answer

thats how i solved it but i dont know if its right

amistre64 · Answer

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amistre64 · Answer

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amistre64 · Answer

your +41 would indicate a -amplitude to start with

amistre64 · Answer

y = -44cos() + 41  if pulled down to start it

y = 44cos() + 85  if pushed up to start it

amistre64 · Answer

.... great, now I gotta think lol

when t=0; cos() = 1

so our +c should be the mid line; or average of 85 and 41 right?

amistre64 · Answer

y = +- 22cos(...) + 63  would account for up or down

our range is 44, half that is the amplitude :)