A 25-kg television set rests on four rubber pads that are on the floor, each one having a height of 1.0 cm and a radius of 0.60 cm. A horizontal force is applied to the television set. When the pads are just at the point of sliding over the floor, how far has the television set moved sideways due to the deformation of the pads? The coefficient of static friction between the rubber and the floor is 1.0 and the shear modulus of these rubber pads is $2.6 \times 10 ^ { 6 } \mathrm {~Pa}$
A) 8.4 mm
B) 1.1 mm
C) 4.2 mm
D) 2.1 mm
E) 16 mm

Question

A 25-kg television set rests on four rubber pads that are on the floor, each one having a height of  1.0 cm and a radius of  0.60 cm. A horizontal force is applied to the television set. When the pads are just at the point of sliding over the floor, how far has the television set moved sideways due to the deformation of the pads? The coefficient of static friction between the rubber and the floor is  1.0  and the shear modulus of these rubber pads is $2.6 \times 10 ^ { 6 } \mathrm {~Pa}$
A)  8.4 mm
B)  1.1 mm
C)  4.2 mm
D)  2.1 mm
E)  16 mm

Quizplus · Accepted Answer

The force of static friction is equal to the weight of the television set times the coefficient of static friction. The deformation of the pads can be calculated using the shear modulus formula, and the correct calculation gives a sideways movement of 2.1 mm.

A 25-Kg Television Set Rests on Four Rubber Pads That 2.6×106 Pa2.6 \times 10 ^ { 6 } \mathrm {~Pa}2.6×106 Pa

A 25-Kg Television Set Rests on Four Rubber Pads That $2.6 \times 10 ^ { 6 } \mathrm {~Pa}$