# Three people pull simultaneously on a stubborn donkey. Jack pulls eastward with a force of 90.7 N, Jill pulls with 89.1 N in the northeast direction, and Jane pulls to the southeast with 175 N. (Since the donkey is involved with such uncoordinated people, who can blame it for being stubborn?) Find the magnitude of the net force the people exert on the donkey.

What is the direction of the net force? Express this as the angle from the east direction between 0° and 90°, with a positive sign for north of east and a negative sign for south of east.

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1. This is a routine vector addition problem.

Separately add the x (east) and y (north) components of the three force vectors.

Fjack,x= 90.7
Fjack,y = 0
Fjill,x= 89.2 cos45 = 63.07
Fjill.y = 89.2 sin45 = 63.07
Fjane,x = 175cos45 = ______
Fjane,y = -175cos45 = ______

For the resultant,
Fx = Fjack,x + Fjill,x + Fjane,x = ____
Fy = Fjack,y + Fjill,y + Fjane,y = ____

Direction of resultant = arctan Fy/Fx
= ____
Fill in the blanks

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