你是一位物理老师，需要给学生讲解这个题目。要分析每一个运动过程。---**Textual Information:** 42. "智勇大冲关"最后一关有如图所示的滑道，冲关者坐上坐垫（冲关过程中人和坐垫不分离）从A点静止开始沿倾斜直轨道AB滑下，斜道倾角θ=37°; CD是一长L=3m的水平传送带, B与C两点平滑衔接，A点距传送带垂直距离为h=2.4m，冲关者经C点到D点后水平抛出，落在水面上一点E。已知：传送带末端距水面高度H=0.8m，坐垫与AB斜道间动摩擦因数为μ₁=0.5，坐垫与传送带间动摩擦因数为μ₂=0.2，冲关者的质量为m=50kg，坐垫质量忽略不计, sin37°=0.6, cos37°=0.8, g=10m/s²; 求： (1) 冲关者到达B点时的速度大小v_B; (2) 如果传送带不动，求冲关者落到水面E点与D点的水平距离x; (3) 如果传送带速率为1m/s沿逆时针方向转动，求冲关者与传送带之间因摩擦产生的热量Q。 **Chart/Diagram Description:** * **Type:** Schematic diagram illustrating a physics problem setup involving a slide, a conveyor belt, and projectile motion. * **Main Elements:** * **Points:** Points A, B, C, D, and E are labeled. A is the starting point on a slope. B and C are at the junction of the slope and the horizontal section. D is the end of the horizontal section (conveyor belt). E is the landing point in the water. * **Lines:** * A straight line segment labeled AB represents the inclined track. * A straight line segment labeled CD represents the horizontal track/conveyor belt. B and C are shown as connected. * A dashed horizontal line extends from A to the left, indicating a reference level. * A dashed vertical line extends downwards from A, labeled with height h=2.4m, ending at the level of the CD track. * A dashed vertical line extends downwards from D, labeled with height H=0.8m, ending at the water surface. * A dashed curved line extends from D to E, representing the trajectory of projectile motion. * A horizontal line represents the water surface, where point E is located. * **Shapes:** A simple representation of a person on a seat is shown at point A. The tracks AB and CD form a combined path. * **Coordinate Axes:** No explicit coordinate axes are shown, but implied vertical and horizontal directions are indicated by height labels (h, H) and horizontal distance labels (L). * **Angles:** An angle of 37° is labeled between the inclined track AB and the horizontal direction (indicated by the dashed line extending from A). * **Labels and Annotations:** * Points are labeled A, B, C, D, E. * Heights are labeled h=2.4m and H=0.8m. * The length of the CD segment is labeled L=3m. * The angle of the slope AB is labeled 37°. * Arrows indicate the vertical direction for heights h and H. * An arrow with text "L=3m" indicates the horizontal length of CD. * **Relative Position and Direction:** A is higher than B and C. B and C are at the same horizontal level as D. D is higher than E (water surface). The slope AB goes downwards from A to B. The track CD is horizontal. The trajectory from D to E is a downward curve. * **Legend:** None.