Physics(Please help)
posted by Hannah .
Some bacteria are propelled by motors that spin hairlike flagella. A typical bacterial motor turning at a constant angular velocity has a radius of 1.9x108m, and a tangential speed at the rim of 2.7x105 m/s. (a) What is the angular speed (the magnitude of the angular velocity) of this bacterial motor? (b) How long does it take the motor to make one revolution?
I do not know how to start this. Thank you!
v=ù•R, => ù=v/R,
T=2ð/ù
So is v 1.9e^8?? I do not know what r is.

angular speed ω.
linear speed v.
v=ω•R, => ω=v/R,
R=1.9x108 m,
v=2.7x105 m/s.
Time for 1 rev = period T,
T=2π/ω