Keys with a combined mass of 0.100 kg are attached to a 0.25m long string and swung in a circle in the vertical plane.(adsbygoogle = window.adsbygoogle || []).push({});

a) What is the slowest speed that the keys can swing and still maintain a circular path?

b) What is the tension in the string at the bottom of the circle?

for part a, I used g= v^2/r and rearranged it to v=sqrt(gr)

I got v=2.5 m/s

I'm pretty sure that's right

I think i'd have to use the same equation for the part b?

I'm just stuck on the radius thing for part b

any ideas would be great

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# Homework Help: Circular Motion of keys

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