Acentrifuge is used to test space pilots. the centrifuge spins with a centripetal acceleration of 6.54 g. if the length of the centrifuge's arm is 15 m, what is the speed of the centrifuge?

The centripetal acceleration is calculated using the following rule:
C = (v^2) / (r)
where:
C is the centripetal acceleration = 6.54 g = 6.54 * 9.8 = 64.092 m/sec^2
v is the speed of the centrifuge that we want to calculate
r is the radius of radius (length of centrifuge arm) = 15 m

Substitute with the givens to get the speed as follows:
64.092 = (v^2) / 15
v^2 = 961.38
v = 31.006 m/sec

The formula for centripital acceleration is:
a= v²/r, where v is the speed of the object, and r is the length from the center of the system. 

a is in g, rather than m/s/s, so we convert:
6.54g * 9.8m/s²/1g = 64.09m/s²

Plugging in our values: 
64.09 = v²/15                      Multiply both sides by 15
961.38 = v²
v = 31m/s