A 55-kg box rests on a horizontal surface. The coefficient of static friction between the box and the surface is 0.30. A 140-N force is applied to the box. What is the frictional force on the box?

161.7N

Explanation:

Given parameters:

Mass of the box  = 55kg

Coefficient of friction  = 0.3

Applied force  = 140N

Unknown:

Frictional force on the box = ?

Solution:

The frictional force on the box is a force that opposes the motion of the box.

To find the value of this force;

        Fr  = u m g

u is the coefficient of static friction

m is the mass

g is the acceleration due to gravity

 So;

     Fr  = 0.3 x 55 x 9.8  = 161.7N

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i had a friend that had sleep paralysis and he told me a story one time where he was laying in bed and he couldn't move his body no matter how hard he tried and there was someone standing in the corner of his room coming towards him. he couldn't move and you can't "wake up" because you are already conscious. sometimes sleep paralysis can be triggered by frequent waking up during the night based off of multiple trips to the bathroom, or if you had ever been abused, sleep paralysis can start happening from things like that.