# College Physics

posted by .

Some bacteria are propelled by motors that spin hair-like flagella. A typical bacterial motor turning at a constant angular velocity has a radius of 1.1x10-8m, and a tangential speed at the rim of 2.0x10-5 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 was able to answer a) but I am not sure what equation to use for part b. Below is what I have calculate. A helpful nudge in the right way would be great!

VT = 2.0x10-5 m/s
r = 1.1x10-8m

a)w = (2.0x10-5 m/s = 1.1x10-8m)t

• College Physics -

a) angular speed = w = V/R
b) Period = (2 pi)/w = 3.36*10^-3 s

• College Physics -

Thank you!

You answer is correct. My calculator is giving me 0.00345. I am not sure why. Do you think that it could be a setting that I need to change?

• College Physics -

Never mind - I figured it out.

• College Physics -

my calculator is giving me 0.00345. How did you figure it out?

## Similar Questions

1. ### physics

(a) What is the tangential acceleration of a bug on the rim of a 6.0 in. diameter disk if the disk moves from rest to an angular speed of 79 rev/min in 5.0 s?
2. ### physics

The flywheel of a steam engine runs with a constant angular speed of 164 rev/min. When steam is shut off, the friction of the bearings and the air brings the wheel to rest in 1.6 h. I figured out the constant angular acceleration=1.71 …

The angular speed of a large pulley wheel that has a radius of 15, is 50 revolutions/min. Find the angular speed and the rim speed of the smaller wheel that has a radius of 5. The rim speed is going to be the same. I got the angular …
4. ### physics

A car is up on a hydraulic at a garage. The wheels are free to rotate, and the drive wheels are rotating with a constant angular velocity. Does a point on the rim of the wheel have (A) a tangential velocity, (B) a tangential acceleration …
5. ### physics

Some bacteria are propelled by biological motors that spin hair-like flagella. A typical bacterial motor turning at a constant angular velocity has a radius of 1.70e-8 m, and a tangential speed at the rim of 2.32 e-5 m/s. a) What is …
6. ### Physics

Some bacteria are propelled by motors that spin hair-like flagella. A typical bacterial motor turning at a constant angular velocity has a radius of 1.9x10-8m, and a tangential speed at the rim of 2.5x10-5 m/s. (a) What is the angular …