Solving Column Reactions with an Offset Load

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To solve for the magnitude of force f1 and the reaction at pin support A, begin by resolving all applied forces into their x and y components using trigonometric functions. Apply the three equations of equilibrium: the sum of forces in the x direction equals zero, the sum of forces in the y direction equals zero, and the sum of moments about point A equals zero. Consider the 5kN force offset by 0.5 m horizontally, as it generates a moment about point A. Calculate the moments by multiplying the force by the perpendicular distance from the line of action to point A. This approach will yield the necessary values for f1 and the reaction forces at A.
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A column AB is anchored to the ground by a pin-joint at A, and is held in a vertical position by various loads as shown. Determine:
(i) Magnitude of force f1
(ii) Magnitude and direction of the reaction at A

I know how to calculate F1 if it was on a horizontal or vertical. But I'm not sure How to calculate it with the 5kN force offset by 0.5 m horizontally. We haven't been taught how to calculate with anything like this yet.
 

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At the pin support A, there are 2 unknown force components, Ax in the horizontal direction and Ay in the vertical direction. I am sure you are familiar with the three equations of equilibrium,
sum of forces in x direction = 0
sum of forces in y direction, and
sum of moments about any point =0.
You should first resolve all applied forces, known or unknown, into their x and y components, Fcos theta and Fsin theta, respectively, each applied at the known points. Then sum moments about support A = 0 , paying attention to clockwise vs. counterclockwise moments. Note that the 5kN offset force also produces a moment about A. The moment of a force about a point (axis) is the product of the force times the perpendicular distance from the line of action of the force to that point.
 

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