# physics

posted by
**becky**
.

hi i have a physics question i don't understand

here is the question

A sample of blood is placed in a centrifuge of radius 15 cm. the mass of the corpuscle is 3.0*10^-16 kg, and the magnitude of the force required to make it settle out of the plasma is 4.0X10^-11 N. At how many revolutions per second should the centrifuge be operated?

thanks

Force= centripetal force

Force= m(radius*angular speed)

r is in meters.

solve for angular speed, it will be in radians/sec. To convert it to rev/sec, divide by 2pi.