Four forces are acting on an object. Force 1 has a magnitude of 5N at an angle of 70° above the +x-axis; force 2 has a magnitude of 8N at an angle of 35° above the +x-axis; force 3 has a magnitude of 4N at an angle of 20° above the -x-axis; force 4 has a magnitude of 7N at an angle of 25° to the left of the -y-axis. Find the magnitude and direction of the resultant of these four forces. Find the resultant force, direction angle (in degrees), and direction.

Question

Henry · Answer

Fr = 5N[70o] + 8[35] + 4[20] + 7[245]

X=5*Cos70 + 8*Cos35 + 4*Cos20 + 7*Cos245
= 9.1 N.
Y=5*sin70 + 8*sin35 + 4*sin20 +7*sin245
= 4.31 N.

Tan A = Y/X = 4.31/9.1 = 0.47583
A = 25.4o CCW = Direction.

Fr = X/Cos A = 9.1/Cos25.4 = 10.0 N. @
25.4o = Resultant force.

Kabwe Musonda · Answer

£fy=4•31100N £fx=9.063N Direction =24 degrees