1. **Problem Statement:** Determine the support reactions at point A for the beam with a collar that can slide vertically, subjected to a 900 N downward force at the center, a 500 N·m clockwise moment at the center, and geometry as described.
2. **Free Body Diagram and Known Data:**
- Vertical force at center: $F = 900$ N downward
- Moment at center: $M = 500$ N·m clockwise
- Lengths: $1.5$ m from A to center, $1.5$ m from center to bend, $1$ m from bend to B
- Beam angle at bend: $45^\circ$
- Collar at A can slide vertically, so vertical reaction $A_y$ exists, but horizontal reaction $A_x$ is zero (no horizontal restraint).
3. **Reactions to find:**
- Vertical reaction at A: $A_y$
- Horizontal reaction at A: $A_x = 0$ (since collar slides vertically)
4. **Equilibrium Equations:**
- Sum of vertical forces: $$\sum F_y = 0 = A_y - 900$$
- Sum of horizontal forces: $$\sum F_x = 0 = A_x = 0$$
- Sum of moments about A: $$\sum M_A = 0$$
5. **Calculate moment arm for the 900 N force:**
- The 900 N force acts at center, $1.5$ m from A along the beam.
- The beam is horizontal from A to center, so moment arm is $1.5$ m vertically.
6. **Calculate moment arm for the 500 N·m moment:**
- Moment is applied at center, so it directly adds to moment equilibrium.
7. **Calculate moment from the 900 N force about A:**
$$M_{900} = 900 \times 1.5 = 1350 \text{ N}\cdot\text{m (clockwise)}$$
8. **Sum moments about A:**
Taking clockwise as positive,
$$\sum M_A = 1350 + 500 - M_{A_y} = 0$$
9. **Moment due to vertical reaction $A_y$ at A:**
- Since $A_y$ acts at A, its moment arm is zero, so it produces no moment.
10. **Check for other moments:**
- No other forces produce moments about A.
11. **Solve for $A_y$ from vertical forces:**
$$A_y - 900 = 0 \Rightarrow A_y = 900 \text{ N (upward)}$$
12. **Check moment equilibrium:**
$$1350 + 500 = 1850 \neq 0$$
This indicates the beam is not in equilibrium with only $A_y$ reaction.
13. **Consider horizontal reaction $A_x$:**
- The collar can slide vertically, so $A_x$ can exist.
- The beam is angled at $45^\circ$ from the center to B, so the force at B can create horizontal reaction at A.
14. **Resolve forces at B:**
- Since no external force at B, reaction at B is zero.
15. **Reconsider moment arm for $A_y$:**
- The beam is horizontal from A to center, so $A_y$ does not create moment about A.
16. **Moment equilibrium must be balanced by a horizontal reaction at A:**
- Let $A_x$ be the horizontal reaction at A.
- The vertical shaft allows vertical sliding, so $A_x$ can exist.
17. **Calculate moment arm of $A_x$ about A:**
- $A_x$ acts horizontally at A, so no moment arm about A.
18. **Moment equilibrium must be balanced by a moment reaction at A:**
- Since collar is fixed to member, it can resist moment.
19. **Let $M_A$ be the moment reaction at A:**
- Sum moments about A:
$$1350 + 500 - M_A = 0 \Rightarrow M_A = 1850 \text{ N}\cdot\text{m (counterclockwise)}$$
20. **Summary of reactions:**
- $A_x = 0$ (no horizontal force)
- $A_y = 900$ N upward
- $M_A = 1850$ N·m counterclockwise
**Final answer:**
$$A_x = 0, \quad A_y = 900 \text{ N (upward)}, \quad M_A = 1850 \text{ N}\cdot\text{m (counterclockwise)}$$
Support Reactions 30A872
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.