a body is pulled over a surface by applying 20 Newton making an angle 60 degree with the horizontal.if the body moves with constant speed on a rough surface on which coefficient of friction is .4 then the mass of the body is?

Answer 1

horizontal pull = 20 cos 60 = 10 N
vertical pull up = 20 sin 60 = 17.3 N

normal force = m g - 17.3

friction force = .4 (9.81 m - 17.3)
= 3.92 m - 6.92

so
3.92 m - 6.92 = 10