1. **Problem Statement:**
A 12 m long beam with negligible weight has a 13 kN crate at point C, which is 2 m from the right end (point B). We need to find the reaction forces at point A.
2. **Setup and Known Values:**
- Length of beam, $L = 12$ m
- Load at point C, $F = 13$ kN
- Distance from point C to point B, $d_C = 2$ m
- Distance from point C to point A, $L - d_C = 12 - 2 = 10$ m
3. **Assumptions:**
- Beam is simply supported at points A and B.
- Weight of beam is negligible.
- Reaction forces at A and B are vertical and denoted as $R_A$ and $R_B$ respectively.
4. **Equilibrium Equations:**
- Sum of vertical forces: $$R_A + R_B = 13$$
- Taking moments about point A (counterclockwise positive): $$R_B \times 12 = 13 \times 10$$
5. **Calculate $R_B$:**
$$R_B = \frac{13 \times 10}{12} = \frac{130}{12} = 10.8333$$ kN
6. **Calculate $R_A$ using vertical forces sum:**
$$R_A = 13 - R_B = 13 - 10.8333 = 2.1667$$ kN
7. **Round to tenths:**
$$R_A = 2.2 \text{ kN}$$
**Final answer:**
The reaction force at point A is $\boxed{2.2}$ kN.
Beam Reaction 235801
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