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
w = 1818.18 rad/s

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

  • College Physics -

    a) angular speed = w = V/R
    = 2*10^-5/1.1*10^-8 = 1818 rad/s
    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.

    Thanks for your help!

  • College Physics -

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

Respond to this Question

First Name
School Subject
Your Answer

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 …
  3. Radians

    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 …
  7. Physics(Please respond)

    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 2.7x10-5 m/s. (a) What is the angular …
  8. Physics(Please help)

    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 2.7x10-5 m/s. (a) What is the angular …
  9. physics

    A disk with mass m = 8.1 kg and radius R = 0.33 m begins at rest and accelerates uniformly for t = 18 s, to a final angular speed of ω = 34 rad/s. What is the angular acceleration of the disk?
  10. Physics

    A uniform disk with mass 6 kg and radius 1.8 m is pivoted at its center about a horizontal, frictionless axle that is stationary. The disk is initially at rest, and then a constant force 31.5N is applied to the rim of the disk. The …

More Similar Questions