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physics - mass spring systems question

Hi, I can't seem to work out this problem/ what formulas to use:

An object was suspended from the end of vertical spring and set into ocsillating motion along a vertical line with acceleration (a) at a displacement (x) was given by a=-360x.
Calculate:

i) frequency

ii) time period of the oscillations.


The previous question, which it was related had a time period of 0.325sec ( 20 oscillations in 6.5 sec) and freq of 3.08Hz. [ checked with book answers]. They say the mass is changed in this question though.


Thank you! :smile:
Original post by igloo1
Hi, I can't seem to work out this problem/ what formulas to use:

An object was suspended from the end of vertical spring and set into ocsillating motion along a vertical line with acceleration (a) at a displacement (x) was given by a=-360x.
Calculate:

i) frequency

ii) time period of the oscillations.


The previous question, which it was related had a time period of 0.325sec ( 20 oscillations in 6.5 sec) and freq of 3.08Hz. [ checked with book answers]. They say the mass is changed in this question though.


Thank you! :smile:


You need to find ω to get the frequency.
There is a formula that relates ω2 to the acceleration of the mass and its displacement from equilibrium. (It's the defining formula for SHM)
Reply 2
Original post by Stonebridge
You need to find ω to get the frequency.
There is a formula that relates ω2 to the acceleration of the mass and its displacement from equilibrium. (It's the defining formula for SHM)


so w=2pi(f) and a=-w^2 x.
i would work out f, but I dont know w? Sorry, I'm still a bit confused.. :s-smilie:
Original post by igloo1
so w=2pi(f) and a=-w^2 x.
i would work out f, but I dont know w? Sorry, I'm still a bit confused.. :s-smilie:


you know
a = -w2x
that's correct

and you are given in the question that
a = -360x

So what is w?
Reply 4
Original post by Stonebridge
you know
a = -w2x
that's correct

and you are given in the question that
a = -360x

So what is w?


-6x10^0.5?
Original post by igloo1
-6x10^0.5?



If
a = -(w2)x, and
a = -(360)x

The two terms in the brackets in the two equations must be equal.

So what is w2 equal to?
Hence what is w equal to?
Hence what is f?
Reply 6
Original post by Stonebridge
If
a = -(w2)x, and
a = -(360)x

The two terms in the brackets in the two equations must be equal.

So what is w2 equal to?
Hence what is w equal to?
Hence what is f?


ohh I see. Thank you! :biggrin:

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