Question

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

Answer 1

As we know that work `= int_(x_1)^(x_2) vecF.vec (dx)`
Here `F=4xx10xx (5+tanx)=40xx(5+tanx)`
`:.W=int_-((5pi)/12)^(pi/4)40(5+ tanx)dx`
`=200xx(pi/4-(-(5pi)/12))+40[lnsec (pi/4)-lnsec (-(5pi)/12)]`
Now simplify it...