A dray horse is being pulled by a rope across a level plow field by a force of 750.0N exerted at an angle of 47° above the horizontal. If the horse’s velocity is constant and the coefficient of friction is ì=.21, determine the mass of the horse.

Answer 1

Wt. = m*g = m*9.8 = Wt. in Newtons.

Fp = 9.8m*sin(0) = 0 = Force parallel to the field.
Fv=9.8m*cos(0) - 750*sin47 = 9.8m-548.5=
Force perpendicular to the field.

Fk = u*Fv=0.21(9.8m-548.5)=2.06m-115.19 = Force of kinetic energy.

750*cos47-Fp-Fk = m*a
511.5-0-(2.06m-115.19) = m*0
511.5 - 2.06m+115.19 = 0
2.06m = 626.7
m = 304 kg.