Question
Please expalin the reason behind your answers.
The cellular motor driving the flagellum in E. coli exerts a typical torque of 360pN middot nm on the flagellum. If this torque results from a force applied tangentially to the outside of the 15nm -radius flagellum, what's the magnitude of that force? Express your answer to two significant figures and include the appropriate units. A car tune-up manual calls for tightening the spark plugs to a torque of 30.0N middot m. To achieve this torque, with what force must you pull on the end of a 21.0cm -long wrench if you pull (a) at right angles to the wrench shaft and (b) at 109 degree to the wrench shaft?
Explanation / Answer
10.53 T = F*r
360*10^-12*10^-9 = F*15*10^-9
F = 24pN
10.22
F = 30/0.21 = 142.85N
F(theta) = 30/(0.21*cos19) = 151N