视频演示解题步骤，并引导学习---**Extracted Content:**
**Question Number:** 12
**Question Stem:**
质量分布均匀的实心正方体 A、B 置于水平桌面上，如图甲所示。将 B 沿水平方向截取高为 h 的柱体，并将该柱体叠放在 A 上，A、B 剩余部分对桌面的压强 p 随截取高度 h 的变化关系如图乙所示，则 B 的密度为 _______ kg/m³, A 的重力为 _______ N. (g 取 10 N/kg)
**Translation of Question Stem:**
Uniformly distributed solid cubes A and B are placed on a horizontal table, as shown in Figure 甲. A column of height h is cut horizontally from B, and this column is placed on A. The relationship between the pressure p exerted by the remaining parts of A and B on the table and the cut height h is shown in Figure 乙. Then the density of B is _______ kg/m³, and the weight of A is _______ N. (g is taken as 10 N/kg)
**Other Relevant Text:**
* A QR code is present with the text "精题详解" (Detailed explanation of the problem).
* The gravitational acceleration `g` is given as 10 N/kg.
**Chart/Diagram Description:**
**Diagram 甲 (Jia):**
* **Type:** Schematic diagram showing the initial setup.
* **Main Elements:**
* Two solid objects, labeled "A" and "B", are depicted. They appear to be cubes of the same size.
* Both objects are resting side-by-side on a horizontal surface. The surface is indicated by a series of short diagonal lines.
* The diagram is labeled "甲" at the bottom center.
**Diagram 乙 (Yi):**
* **Type:** Line graph.
* **Main Elements:**
* **Coordinate Axes:**
* **Horizontal Axis (X-axis):** Labeled "h/cm", representing the height `h` (in centimeters) of the column cut from B. The scale ranges from 0 to 10 cm.
* **Vertical Axis (Y-axis):** Labeled "p/(×10² Pa)", representing the pressure `p` (in units of 10² Pascals). The scale ranges from 0 to 8 (implying 0 to 8 × 10² Pa).
* **Data Lines (Series):**
* **Line A:** Represents the pressure exerted by object A on the table. It is an upward-sloping straight line.
* Initial point (h=0 cm): p_A = 4 × 10² Pa.
* End point (h=10 cm): p_A = 8 × 10² Pa.
* **Line B:** Represents the pressure exerted by the remaining part of object B on the table. It is a downward-sloping straight line.
* Initial point (h=0 cm): p_B = 6 × 10² Pa.
* End point (h=10 cm): p_B = 0 Pa.
* **Intersection Point:** The two lines A and B intersect at the point where h = 2 cm. At this intersection, both p_A and p_B are equal to 5 × 10² Pa.
* **Labels and Annotations:**
* The lines are clearly labeled "A" and "B".
* The graph is labeled "乙" at the bottom right.
* There are some handwritten blue marks on the graph, such as "101", "132", and "113." which appear to be external annotations and not part of the problem's official content.