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The answer is 4.1 m

How do you do this problem I am pulling my hair out with these kind of physics problems. Any help would be appreciated. Thank you

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- Thread starter hansen44
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The answer is 4.1 m

How do you do this problem I am pulling my hair out with these kind of physics problems. Any help would be appreciated. Thank you

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The answer is 4.1 m

How do you do this problem I am pulling my hair out with these kind of physics problems. Any help would be appreciated. Thank you

This is in relation to centripetal force. They basically want you to relate how the static coefficient of friction and centripetal force work. It sounds kind of tricky, but if you just draw a diagram, the answer will come to you.

The coeffecient of friction is what is making the cyclist stay inside of the circle, and the equation is equal to uk * Fn. The only other force is the F = m x a and the acceleration is the centripetal force.

Thus

fn = F

ukFn = m x a

uk mg = m a (a = centripetal force = v^2/r)

The masses cross each other out and you have

ukg = a

now all you need to do is calculate for R. Remember, you also need to convert km/h into m/s.

0.5 x 10 = X/R

10 km/hr * 1000m/km * 1hr/60min * 1min/60 seconds = 2.8 m/s

- edit -

wait 4.1 m/s? Did you give us the correct values?

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Is this from the kaplan book? Because it says 10 miles/ hr.Yes I gave you the right answer, thats why im so confused. I got the same answer you did. Anyone understand this?

10km/hour = 10⁴m/hr x hr/60min x min/60s = 2.78 m/s

The answer is 4.1 m

How do you do this problem I am pulling my hair out with these kind of physics problems. Any help would be appreciated. Thank you

Fc=mv²/r = μmg= Fs

v²/r = μg

r=v²/μg = (2.78m/s)²/(0.5 x 10m/s²

r = 7.72m²/s² / 5m/s² = 1.54m

Well, that answer doesn't match 4.1m. Don't know what to tell ya.

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This seems exactly right to me...but, the only way to get the right answer is if it was 10 miles/hour. One mile=1.6 kilometers, and you end up with r=4.1. But, basically, it's a stupid question (because of the conversion). If you understood what tnckem did, you're good to go.10km/hour = 10⁴m/hr x hr/60min x min/60s = 2.78 m/s

Fc=mv²/r = μmg= Fs

v²/r = μg

r=v²/μg = (2.78m/s)²/(0.5 x 10m/s²)

r = 7.72m²/s² / 5m/s² = 1.54m

Well, that answer doesn't match 4.1m. Don't know what to tell ya.

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Because it is 10 miles/hr. Either the op got a typod book or someone gave him the question incorrectly.10km/hour = 10⁴m/hr x hr/60min x min/60s = 2.78 m/s

Fc=mv²/r = μmg= Fs

v²/r = μg

r=v²/μg = (2.78m/s)²/(0.5 x 10m/s²)

r = 7.72m²/s² / 5m/s² = 1.54m

Well, that answer doesn't match 4.1m. Don't know what to tell ya.

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I second 1.542 m.

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