A cubical block of side 0.4 m slides on an oiled (μ = 8 poise) plane horizontal surface. The oil film between block and cube surface has a uniform thickness of 0.4 mm. What force is required to drag block at 4 m/s?
1
1.28 kN
2
1.64 kN
3
1.92 kN
4
2.56 kN