生成解题视频---```plain text **Problem 2** **Introduction:** 万唯原创 Electric vehicles are a green and environmentally friendly mode of transportation, using batteries as a power source. The safety of the battery mainly depends on temperature control; the car's battery is divided into multiple groups, and when the temperature of a certain group is too high, the cooling system will be activated to cool it down, so that the temperature of the battery pack is maintained within a safe range. Figure 甲 shows a simulation diagram of the temperature control system of a certain electric vehicle. The power supply voltage of the control circuit is a constant 6 V, R_t is a thermistor, and the relationship between its resistance and temperature t is shown in Figure 乙. The maximum resistance of the sliding rheostat R_p is 300 Ω. When the current in the control circuit is greater than or equal to 20 mA, the relay attracts and the cooling system works. **Diagram 甲 Description:** Type: Circuit Diagram. Main Elements: - Power Supply: Labeled 6V, connected to switch S. - Switch: Labeled S. - Resistors: Sliding Rheostat R_p, Thermistor R_t. Connected in series with the relay coil and switch S across the power supply. - Relay: Coil is in series with R_p, R_t, and S. Has a movable contact and fixed contacts a and c. The movable contact is connected to terminal b of the cooling system. - Cooling System: Labeled "制冷系统", connected to contact b of the relay. - Fan: Labeled "吹风". - Labels: R_p, R_t, S, a, b, c, 6V, 制冷系统, 继电器, 吹风. **Diagram 乙 Description:** Type: Line Chart (Curve). Main Elements: - X-axis: Labeled "t/℃", representing temperature in degrees Celsius. Scale from 0 to 140 in increments of 20. - Y-axis: Labeled "R/Ω", representing resistance in Ohms. Scale from 0 to 200 in increments of 40. - Curve: Shows the relationship between resistance R and temperature t, showing that resistance decreases as temperature increases. - Data Points: Two points are labeled with coordinates (t, R): (60, 70) and (90, 40). - Title: 第2题图 (Diagram for question 2). **Question (1):** (1) 图甲中应将制冷器接线柱 b 与触点 _______ (选填“a”或“c”)相连。 (1) In Figure 甲, the cooling system terminal b should be connected to contact _______ (select "a" or "c"). **Question (2):** (2) 小明想利用一只电阻箱在室温条件下对上述电路进行调试,使电路能在 60 ℃时启动制冷系统。他先将电阻箱调为 70 Ω,然后进行如下操作。 步骤一: 断开开关, _______ ,并用电阻箱替换热敏电阻; 步骤二: 闭合开关,调节滑动变阻器的滑片,直到 _______ ; 步骤三: 断开开关,用热敏电阻替换电阻箱,完成电路调试。 (2) Xiao Ming wants to use a resistance box under room temperature conditions to debug the above circuit so that the cooling system can be started at 60 ℃. He first adjusts the resistance box to 70 Ω, and then performs the following operations. Step one: Disconnect the switch, _______ , and replace the thermistor with the resistance box; Step two: Close the switch, adjust the slider of the sliding rheostat, until _______ ; Step three: Disconnect the switch, replace the resistance box with the thermistor, and complete the circuit debugging. **Problem 3** **Introduction:** 精练本 (3) 小明观察到家里电动汽车的电池容量为 500 Ah,电池电压为 300 V,若该电动汽车在平直公路上匀速行驶时受到的阻力为 600 N,电池充满电,电动汽车将电池储存电能的 80%转化为机械能,该车最多能行驶的路程是多少? (3) Xiao Ming observed that his family's electric car has a battery capacity of 500 Ah and a battery voltage of 300 V. If the electric car is driving at a constant speed on a flat road and is subjected to a resistance force of 600 N, when the battery is fully charged, the electric car converts 80% of the stored electrical energy into mechanical energy. What is the maximum distance the car can travel? **Problem 4** **Introduction:** 精练本 (4) 小明想探究纯电动汽车和燃油汽车相比,谁更省钱,于是收集了如下资料: (4) Xiao Ming wanted to investigate which is cheaper to drive, a pure electric car or a gasoline car, so he collected the following data: **Table Description:** Type: Data Table. Headers: 项目 | 纯电动汽车 | 燃油汽车 Data: - 每百公里能耗 | 20 kW·h | 8 L - 单位能耗价格 | 1.5 元/度 | 8.3 元/L **Question:** 两种车型的汽车同样行驶 100 公里,在能源消耗上哪种更省钱? When the two types of vehicles travel the same distance of 100 kilometers, which one is cheaper in terms of energy consumption? ```