3．带着忧虑的表情______________________________________________________________

1. 大规模地_________________________　 2. 等同于做某事___________________________

28. A. gracefully 　　　B. emotionally 　　C. academically 　D. financially 　29. A. free from　　 　B. isolated from 　　C. related to 　　　D. close to 　30. A. providing 　　　B. making 　　　　　C. taking 　　　　D. losing

语法填空(时间：10分钟)

Carrying Faggots to Put Out a Fire In the last years of the Warring States period, the State of Qin attacked the State of Wei ____31_____ a large scale repeatedly and occupied large areas of land. In 273 B.B., the Qin army launched another attack upon the State of Wei. The king of the State of Wei summoned ____32_____officials,and asked with a ____33_____ (worry) look if anyone could propose a way to defeat the Qin army. Most of the officials persuaded the king to sue for peace, at the cost of giving away to the State of Qin the large area of land. However, Su Dai, a counsellor, did not agree. "Once there was a man ____34_____ house was on fire. People told him to put out the fire with water, but he would not listen. ____35_____, he carried a faggot to put out the fire, only to make the fire ____36_____ (fierce). That was ____37_____ he didn't know that,instead of putting out the fire, faggots could only make it burning more vigorously. Isn't it equal to ____38_____ (carry) faggots to put out a fire if you agree to sue for peace at the cost of the land of the State of Wei?"Though Su Dai's argument was very convincing, the king accepted the ____39_____ (suggest) of those officials and gave away to the State of Qin a large area of the land of the State of Wei. ____40_____ might be expected, the Qin army attacked the State of Wei on a large scale in 225 B.C. The State of Wei was finally destroyed by the State of Qin.

积累短语：

10．如图甲所示，abcd为导体做成的框架，其平面与水平面成θ角，质量为m的导体棒PQ与ab、cd接触良好，回路的总电阻为R，整个装置放在垂直于框架平面的变化磁场中，磁场的磁感应强度B的变化情况如图乙所示(取图中B的方向为正方向)。而PQ始终保持静止．则下列关于PQ与框架间的摩擦力在时间0-t₁内的变化情况的说法中，有可能正确的是　　　　　　　　　　 (　 AC )

A．一直增大　　　　　 B．一直减小

C．先减小，后增大　　 D．先增大，后减小

9．图中甲为在温度为10℃左右的环境中工作的某自动恒温箱原理简图，箱内的电阻R₁ = 20 K 、R₂ =10K、R₃＝40K，R₁为热敏电阻，它的电阻随温度变化的图线如图乙所示。当 a、b端电压 U_ab 0时，电压鉴别器会令开关S接通，恒温箱内的电热丝发热，使箱内温度升高；当a、b端电压U_ab＞0时，电压鉴别器会令开关S断开，停止加热，则恒温箱内的温度可保持在( C )

A．10℃　　　 B．20℃　　　 C．35℃　　　 D．45℃

8．如图所示，在垂直纸面向里的匀强磁场的边界上，有两个质量和电量均相同的正、负离子(不计重力)，从O点以相同的速度先后射人磁场中，入射方向与边界成θ角，则正、负离子在磁场中(BCD 　)

A．运动时间相同

B．运动轨迹的半径相同

C．重新回到边界时速度的大小和方向相同

D．重新回到边界的位置与O点的距离相等

7．如图示是一种测定导电液体深度的装置：包着一层电介质的金属棒与导电液体形成一个电容器，电容量的变化能反映液面的升降情况 (　 AC　 )

A．电容增大反映h增大

B．电容增大反映h减小

C．将金属棒和导电液体分别接电源两极再断开后，液体深度变化时导电液与金属棒间的电压增大反映h减小

D．将金属棒和导电液体分别接电源两极再断开后，液体深度变化时导电液与金属棒间的电压增大反映h增大

6、如图，用粗细不同的铜导线，制成半径相同的线圈，线圈平面与匀强磁场垂直，让两线圈从有界匀强磁场外同一高度同时自由下落，磁场边界与地面水平，则(　 A 　)．

　　 A. 两者同时落地，且落地速率相同

　　 B．同时落地，粗线圈速率大

　　 C．粗线圈先落地，速率相同

D．粗线圈先落地，且速率大

5、 一金属球，原来不带电，现沿球的直径的延长线放置一均匀带电的细杆AB如图所示，金属球上感应电荷产生的电场在球内直径上a,b,c三点的场强的大小分别为Ea、Eb、Ec,三者相比 ( A　 　)．　

A．Ea最大　　 B．Eb最大　　 C.Ec最大　　 D．Ea=Eb=Ec

4．如右图所示，匀强电场和匀强磁场相互正交，宽度为d，竖直方向足够长。今有一束α粒子以不同的速率沿图示方向射入场区。设α粒子的带电量为q，不计重力，那么飞出复合场区的α粒子的动能变化量可能为(　CD　)

A．　　　B．

C．0　　　　　D．qEd