A sample of blood is placed in a centrifuge of radius 20.0 cm. The mass of a red blood cell is 3.0 10−16 kg, and the magnitude of the force acting on it as it settles out of the plasma is 4.0 10−11 N. At how many revolutions per second should the centrifuge be operated?
rev/s
3 answers
130
Solution or Explanation
Since
Fc = m
vt2
r
= mrω2,
the needed angular velocity is
ω =
Fc
mr
=
sqaure root of (4.0 ✕ 10−11 N)
(3.0 ✕ 10−16 kg)(0.200 m)
= (6.67 ✕ 10 ^2 rad/s) (1 rev/2pi rad) = 1.05x10^6 =>105
Since
Fc = m
vt2
r
= mrω2,
the needed angular velocity is
ω =
Fc
mr
=
sqaure root of (4.0 ✕ 10−11 N)
(3.0 ✕ 10−16 kg)(0.200 m)
= (6.67 ✕ 10 ^2 rad/s) (1 rev/2pi rad) = 1.05x10^6 =>105
sorry i don't know
1 answer