Find Lap Time: Is 0.8 Sec Correct?

[Mushroom79]

Homework Statement

Friction=0.8
r=50 m
T=?

Homework Equations

T=distance/speed

Perimeter=2*pi*r

Fc=(mv^2)/r

Ffriction=m*g*friction

The Attempt at a Solution

Perimeter
2*3.14*50=314

Fc=Ffriction

(mv^2)/r=m*g*friction

v=r*g*friction

= 50*9.82*0.8=391.8

T=314/391.8 = 0.8 s

Is this correct? Seems a bit wrong to me :S

 

[andrien]

forgot to take the square root of velocity.

 

[Mushroom79]

forgot to take the square root of velocity.

Ah! That gives me almost 16 sec, which makes more sense

Thank you!