An object with a mass of 7kg is pushed along a linear path with a kinetic friction coefficient of uk(x)=4+secx. How much work would it take to move the object over #x in [(pi)/8, (5pi)/12], where x is in meters?

1 Answer
Feb 15, 2016

W5,288J

Explanation:

W=5π12π8uk(x)dx=5π12π8(4+secx)dx
W=[4x+ln(secx+tanx)]5π12π8
W=[20π12+ln(sec(5π)12+tan(5π)12)][4π8+ln(sec(π)8+tan(π)8)]
W=[5π3+ln(3,864+3,732)][π2+ln(1,082+0,414)]
W=[5π3+ln(7,596)][π2+ln(1.496)]
W=[5π3+2,028][π2+0,403]
W=[7,261][1,973]
W5,288J