Explanation:
velocity of disc [tex]=\sqrt((gh)/0.75)[/tex]
lets call (h) 1 m to make it simple.
= 3.614 m/s
[tex]\sqrt((4/3) x 1 x 9.8) = 3.614[/tex] m/s pointing towards this:
[tex]4×V_d=\sqrt(4/3hg)[/tex]
[tex]V_h=\sqrt(hg)[/tex]
velocity of hoop=[tex]\sqrt(gh)[/tex]
lets call (h) 1m to make it simple again.
[tex]\sqrt(9.8 x 1) = 3.13[/tex] m/s
[tex]\sqrt(gh) = sqrt(hg)
so [tex]4×V_d= \sqrt(4/3hg)V_h=\sqrt(hg)[/tex]
The disc is the fastest.
While i'm on this subject i'll show you this:
Solid ball [tex]=0.7v^2= gh[/tex]
solid disc [tex]= 0.75v^2 = gh[/tex]
hoop [tex]=v^2=gh[/tex]
The above is simplified from linear KE + rotational KE, the radius or mass makes no difference to the above formula.
The solid ball will be the faster of the 3, like above i'll show you.
solid ball: velocity [tex]=\sqrt((gh)/0.7)[/tex]
let (h) be 1m again to compare.
[tex]\sqrt((9.8 x 1)/0.7) = 3.741[/tex] m/s
solid disk speed [tex]=\sqrt((gh)/0.75)[/tex]
uniform hoop speed [tex]=\sqrt(gh)[/tex]
solid sphere speed [tex]=\sqrt((gh)/0.7)[/tex]
