While moving in, a new homeowner is pushing a box across the floor at a constant velocity. The coefficient of kinetic friction between the box and the floor is 0.368. The pushing force is directed downward at an angle θ below the horizontal. When θ is greater than a certain value, it is not possible to move the box, no matter how large the pushing force is. Find that value of θ.

Question

Physics

Giana Wang

21 September, 14:53

While moving in, a new homeowner is pushing a box across the floor at a constant velocity. The coefficient of kinetic friction between the box and the floor is 0.368. The pushing force is directed downward at an angle θ below the horizontal. When θ is greater than a certain value, it is not possible to move the box, no matter how large the pushing force is. Find that value of θ.

+3

Answers (1)

Know the Answer?

Tristan Ross · Answer 1

Answer: 69.8 degree

Explanation:

F*cos (theta)

is your pushing force projected along the x axis and

-F*0.368*sin (theta)

is the friction force generated by the pressure downwards

when F cos (theta) = F*0.368*sin (theta)

the box wont move no matter how large F is, because you are adding no net force along the x-axis

so sin (theta) / cos (theta) = 1/0.368

tan^-1 (1/0.368) = theta

theta = 69.8 degrees