(adsbygoogle = window.adsbygoogle || []).push({}); [[S.H.M]] Rearranging equations Confusion, Please HELP???

The question that’s got me stuck

Question: A baby of mass = 9kg bounces with a time period of 1.2s in a baby bouncer. What is the spring constant k for the bouncer? Now I know I must rearrange the formula to find k

The formula I/the book used

T = 2π √m ÷ k

I do that and end up with (m × 2π) ÷ T² = k, My book on the other hand rearranges the formula as been (m × 4π²) ÷ T² = k.

Where does the 4π² come from I do not see how 2π changes too 4π², am I missing a rule?

Please help clarify how to get the 4π². I would ask my tutor but he is currently off sick.

My book also does this on the previous question where I am asked to find the value of l in the equation: T = 2π √l ÷ g my book rearranges the equation to (T² × g) ÷ 4π² = k

Again where does the 4π² come from in the original equation.

Thanks you for your help

Jack

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# Homework Help: [[S.H.M]] Rearranging equations Confusion, Please HELP?

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