Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

9. 9 A deli owner creates a lunch special display board by taking a uniform boar

ID: 2245010 • Letter: 9

Question

9.  9

A deli owner creates a lunch special display board by taking a uniform board which has a weight of 222 N, cutting it in half, hinging the halves together with a frictionless hinge, and setting it up as an inverted "V".  Determine the minimum coefficient of static friction needed between the board and the ground in order for her to set the display board up with an angle of 30

A deli owner creates a lunch special display board by taking a uniform board which has a weight of 222 N, cutting it in half, hinging the halves together with a frictionless hinge, and setting it up as an inverted "V". Determine the minimum coefficient of static friction needed between the board and the ground in order for her to set the display board up with an angle of 30 degree between the two sides.

Explanation / Answer

N1 = W/2

N2 = uN1

N2 * L * sin75 = (W/2) * (L/2) * cos75

u * (W/2) * L * sin75 = (W/2) * (L/2) * cos75

u = 1/2 tan75 = 0.134