生成这道题的解析---**Extraction Content** **Question Stem:** 1. 2025年4月28日，全球首艘高速可潜无人艇“蓝鲸号”下水，如图所示。其体积为12m³，依靠智能压载水舱系统进行浮沉调节，可实现数十米深的下潜、静态悬浮和水下航行。(近海海水密度取ρ水) 求： **Image Description:** * **Type:** Photograph. * **Main Elements:** * A submersible vessel is shown, labeled as "蓝鲸号" (Blue Whale). * The vessel is suspended by cables from above, likely being launched or lifted. * The vessel is colored blue and red, with some white and yellow components on top. * It has a streamlined shape, propellers at the rear, and some sensors/antennas on the top structure. * The background appears to be water and some indistinct structures. **Questions:** (1)“蓝鲸号”在近海悬浮时所受浮力； (2)“蓝鲸号”在近海悬浮时，距海面20m处的顶部受到海水的压强； (3)若“蓝鲸号”从近海水平潜行至远海，海水密度突变为1.03 × 10³ kg/m³时，至少应增加多少自重才能防止上浮。 **Other Relevant Text:** * Volume of "蓝鲸号": 12m³ * Depth for question (2): 20m * Density of seawater in question (3): 1.03 × 10³ kg/m³ * Density of seawater in near sea is denoted as ρ水 (rho shui). Note: The value of ρ水 is not explicitly given, but implied as needed for calculations. For question (3), a specific value for the far sea density is given. **Mathematical Formulas/Equations:** * No explicit formulas are written out as equations, but the questions require applying principles of buoyancy (F_buoyancy = ρVg) and hydrostatic pressure (P = ρgh). The density of near sea seawater is given as ρ水, and for far sea it is 1.03 × 10³ kg/m³. The volume V is 12 m³. Depth h for pressure is 20m.