Question: The force F1 = kN and the distributed load w = kN/m. The distances x1 = m, y1 = m, and y2 = m.
Calculate the following:
Part 1: The reaction at "D" - enter sign if negative with no space.
(Answer = )
Part 1: Sum moments about the pinned support "A". This eliminates the unknown horizontal and vertical components of the reaction at that point. Since "D" is a roller the reaction acts perpendicular to the support, in the vertical direction only.
Part 2: "Ax" - the horizontal reaction component at "A" - enter sign if negative with no space.
(Answer = )
Part 2: Sum the horizontal forces and note that there is no horizontal reaction component at "D" since it is a roller support. "Ax" acts to the left and is therefore negative. Do not include a space in the answer.
Part 3: "Ay" - the vertical reaction component at "A" - enter sign if negative with no space.
(Answer = )
Part 3: Sum the vertical forces to determine "Ay" directly. It is strongly recommended that in an examination questions or where no prior feedback is given that the value for "Ay" is checked by taking moments about point "D". This requires some effort but also checks the value for "Ax" and gives good practice at summing moments in a complex ststem.
Part 4: The magnitude of the resultant reaction "A".
(Answer = )
Part 4: The magnitude of the resultant is calculated using the square root of Ax2 + Ay2.
Part 5: The angle of the resultant reaction at "A" - in degrees, and expressed relative to the positive "x" axis.
(Answer = )
Part 5: The angle of the resultant is calculated using tan-1 Ay/Ax. Note that Ax acts to the left and is negative. The resultant therefore lies in the fourth quadrant and has an angle of between 900 and 1800.
Enter the answer to Part 5 in the answer box below:
