Question 515805
<pre>
The formula is 

v<sub>T</sub> = r<font face = "symbol">w</font>

or
     v<sub>T</sub> 
r = ———
     <font face = "symbol">w</font>

The angular velocity <font face = "symbol">w</font> of the second hand is 

60{{{(revolutions)/(hour)}}}

Each revolution is 2<font face = "symbol">p</font> radians.

So 60{{{(revolutions)/(hour)}}} = {{{60*2pi}}}{{{radians/(hour)}}} = {{{120pi}}}{{{radians/(hour)}}} 
 
     v<sub>T</sub> 
r = ———
     <font face = "symbol">w</font>

     {{{100}}}{{{miles/hour}}}
r = ———————————— 
     {{{120pi}}}{{{radians/(hour)}}} 


r = {{{100/(120pi)}}}{{{miles}}} = {{{100/(120pi)}}}{{{"×"}}}{{{5280feet}}} = 1400.5635 feet.

That's the length the second hand would have to be for the tip of it
to be traveling 100 mi/hr.   That's the only one I'll do for now.

Edwin</pre>