## Truss

In the truss diagram below, calculate the reaction at point A.

##
__
__**Hint**

**Hint**

The problem is asking to solve for
$$A_y$$
in the free body diagram below:

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__
__**Hint 2**

**Hint 2**

Due to point A being a roller support, there is only a vertical component force
$$A_y$$
. Point B is a fixed support, so there is both a vertical and horizontal component (
$$B_y$$
and
$$B_x$$
respectively). The problem statement is asking for the reaction at point A, so let's analyze the moments about point B.

The problem is asking to solve for
$$A_y$$
in the free body diagram below:

Due to point A being a roller support, there is only a vertical component force
$$A_y$$
. Point B is a fixed support, so there is both a vertical and horizontal component (
$$B_y$$
and
$$B_x$$
respectively). The problem statement is asking for the reaction at point A, so let's analyze the moments about point B.

Assuming clockwise is positive, the sum of moment about B are zero:

$$$\sum M_B=0$$$

Remember, Moment = Force Applied at Point x Distance to Point

$$$\sum M_B=0=30N(15m)-A_y(15m+15m)$$$

$$$A_y(30m)=450N\cdot m$$$

$$$A_y=\frac{450N\cdot m}{30m}=15\:N$$$

15 N