Question

Clearly draw diagrams and show step by step details on how to solve this problem

2-69. Determine the magnitude and coordinate direction angles of the resultant force, and sketch this vector on the coordinate system. 2 F2 = 125 N 2 60° 45° 60° F1 = 400 N

Answer 1

Resultant Force Fr = (125*4/5* cos 20 degree + 400 cos 45 degree)i + (125*4/5* -sin 20 degree + 400 cos 60 degree) j

+  (125*3/5 - 400 cos 60 degree) k

= 377 i + 167 j - 125 k N

magnitude = sqrt(377^2+167^2+125^2)

= 431 N

direction angle with +x axis , alpha = arccos(377/431) = 29 degree

  with +y axis, beta = arccos(167/431) = 67 degree

  with +z axis gamma = arccos (125/431) = 107 degree