问题 选择题

[3-5](本题共有两个小题,每小题6分,共12分。每小题只有一个选项符合题意)

⑴爱因斯坦提出了光量子概念并成功地解释光电效应的规律而获得1921年的诺贝尔物理学奖。某种金属逸出光电子的最大初动能Ekm与入射光频率ν的关系如图所示,其中ν0为极限频率。从图中可以确定的是______。(填选项前的字母)

A.逸出功与ν有关         

B.Ekm与入射光强度成正比

C.ν<ν0时,会逸出光电子  

D.图中直线的斜率与普朗克常量有关

⑵在光滑水平面上,一质量为m、速度大小为vA球与质量为2m静止的B球碰撞后,A球的速度方向与碰撞前相反。则碰撞后B球的速度大小可能是__________。(题选项前的字母)

A.0.6        B.0.4          C.0.3           D. 0.2

答案

(1)D(2)A

(1)光电子的最大初动能与入射光频率的关系是Ekm = hvW,结合图象易判断D正确。

(2)由碰撞中的动量守恒得mv = 2mvBmvAvA>0,则vB>0.5v,故小于0.5v的值不可能有,A正确。

选择题
阅读理解

Queen Victoria was monarch of Great Britain from 1837 until her death in 1901. This period is often called the Victorian Age.

Queen Victoria was a stern and serious woman. One reason she was so serious was that she had suffered a  great loss. When she was twenty years old, she married a German prince named Albert. Victoria and Albert were deeply in love, and their marriage was extremely happy. In 1861, after they had been married for twenty-one years, Albert died, leaving Queen Victoria heartbroken. For the rest of her life, the lonely Victoria mourned his loss. It was customary in those days for a widow to dress in black for a short time after the death of her husband. But Queen Victoria dressed in black for forty years. And for forty years, as another sigh of her grief, she wrote her letters white paper edged in black.

Even before Prince Albert died, Queen Victoria was known as a very serious woman. She had a strong sense of duty and worked very hard at all her tasks. In her diary she wrote, “I love to be employed; I hate to be idle.” She never forgot that she was Britain’s queen and always acted with great dignity. Victoria had high ideals and moral standards that sometimes made her seem stuffy. She was also very sure of herself. She always thought that she was right, and she expected everyone to agree with her.

小题1:Which of the following statements about Queen Victoria  is NOT true?

A.She had great confidence in herself.

B.She ruled Great Britain for sixty-four years.

C.She enjoyed her marriage to a German prince.

D.She became a serious woman after her beloved husband died.小题2:Queen Victoria wrote her letters on white paper edged in black because______

A.she was a very serious woman.

B.black was her favorite color.

C.that was one way to show her feeling of sadness.

D.it was a custom among monarchs of Great Britain.小题3:All of the following characteristics except ______ can be used to properly describe Queen Victoria.

A.moral

B.lonely

C.workaholic( 工作狂)

D.compromising (妥协)