Alternate Forms of Moment Equation (example continued)

Strategy: Apply Euler's First Law:

In scalar form: A_x = ma_Cx and A_y ˗ W = ma_Cy

A_x = ˗ (3/2) mg [ 1 – sin θ ] cos θ + (3/4) mg cos θ sin θ

Ay ˗ W = ˗ (3/2)mg [ 1 ˗ sin θ ] sin θ ˗ (3/4) mg cos² θ

When the rod is horizontal θ = 0 so

A_x = ˗ (3/2) mg = ˗ (3/2) W (result)

A_y ˗ W = ˗ (3/4) mg = W ˗ (3/4)W = (1/4) W (result)

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