physics!!!!!!!!!!!!!!!!!!!!!!!?
A combination lock has a 1.2 cm}-diameter knob that is part of the dial you turn to unlock the lock. To turn that knob, you grip it between your thumb and forefinger with a force of 0.53 N} as you twist your wrist. Suppose the coefficient of static friction between the knob and your fingers is only 0.11 because some oil accidentally got onto the knob.
What is the most torque you can exert on the knob without having it slip between your fingers?
More Questions From This User See All
Answers & Comments
Verified answer
Ff=u*Fn
Fn= Normal force, which would be .53N.
u=.11, given
Force from friction, maximum = .0583N
Since you would be gripping down on the knob, that friction can be supplied tangentially to the knob. That is where the turning force comes from.
T=F*r,
r=.012m (I dont like cm)
T=.0007N*m
However, note that you would grip with both fingers, not just one.
T=.0014N*m