(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Betty weighs 427 N and she is sitting on

a playground swing seat that hangs 0.22 m

above the ground. Tom pulls the swing back

and releases it when the seat is 0.88 m above

the ground.

The acceleration of gravity is 9.8 m/s2 .

How fast is Betty moving when the swing

passes through its lowest position?

Answer in units of m/s.

2. Relevant equations

KE=1/2 M V^2

PEg=Mgh

i might be missing an equation here

3. The attempt at a solution

i was thinking that potential energy gravitational would turn into Kinetic energy then i solved for v.

PEg= 427 newtons*.66 i used the change in height for h and got 281.82 Joules for my answer. then i said that should transfer to KE.

281.82 joules= 1/2* 427/9.8 Kg * V^2 and i got 11.3737 m/s as my answer. when i checked this it turned out to be wrong. i think i may have to apply circular motion concepts to this problem, but i'm not quite sure how to do that.

thanks in advance.

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# Homework Help: Energy and motion problem

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