Suppose that you are standing on a train accelerating at 0.20g. What minimum coefficient of static friction must exist between your feet and the floor if you are not to slide.

Question

anonymous · Answer

.20 g would be the minimum anything under that you would have started to slide.

anonymous · Answer

|dw:1382063067561:dw|
make sense so far?

anonymous · Answer

let the force on the left be equal to the force felt by acceleration
let the force on the right be equal to the friction force
force_acceleration = force_friction

so then we have
mass*acceleration = u*mass*gravity
or 
m*0.2g = u*m*g
rearrange the equation to solve for coefficient of friction, u
u = 0.2g/g         <- did you see how mass canceled out?