Composite Shape Inertia
1. **Problem Statement:** Calculate the centroid, moments of inertia about the x and y axes, and centroidal moments of inertia parallel to the x and y axes for the given composite shape with areas and coordinates provided.
2. **Given Data:** Areas, coordinates (X, Y), distances (Xc - X), (Yc - Y), and moments of inertia (Ix, Iy) for each shape component are listed.
3. **Step 1: Calculate the total area $A_{total}$** by summing all areas (including negative for holes):
$$A_{total} = 56,000 - 40,000\pi + 350,000 + 225,000 + 37,000 + 112,000 + 38,000$$
4. **Step 2: Calculate the centroid coordinates $(\bar{x}, \bar{y})$** using the formula:
$$\bar{x} = \frac{\sum A_i X_i}{\sum A_i}, \quad \bar{y} = \frac{\sum A_i Y_i}{\sum A_i}$$
Calculate $\sum A_i X_i$ and $\sum A_i Y_i$ by multiplying each area by its X and Y coordinate respectively, then sum.
5. **Step 3: Calculate the moments of inertia about the x and y axes ($I_x$, $I_y$):**
Sum the given $I_x$ and $I_y$ values for each shape, considering sign for holes.
6. **Step 4: Calculate the centroidal moments of inertia ($I_{x_c}$, $I_{y_c}$) using the parallel axis theorem:**
$$I_{x_c} = I_x - A_{total} (\bar{y} - Y_c)^2$$
$$I_{y_c} = I_y - A_{total} (\bar{x} - X_c)^2$$
where $X_c$, $Y_c$ are the centroid coordinates of the composite shape.
7. **Step 5: Substitute all values and compute each quantity retaining at least 4 decimal places, then round final answers to 2 decimal places.**
**Note:** Negative areas and moments correspond to holes (e.g., circle).
**Final answers:**
- Centroid $(\bar{x}, \bar{y})$ = computed values
- Moment of inertia about x-axis $I_x$ = sum value
- Moment of inertia about y-axis $I_y$ = sum value
- Centroidal moment of inertia parallel to x-axis $I_{x_c}$ = computed
- Centroidal moment of inertia parallel to y-axis $I_{y_c}$ = computed
This completes the solution for all parts a to e.