问题
选择题
| 下列说法正确的是（ ） A．在光电效应中，光电子的最大初动能与入射光的频率成正比 B．光是高速运动的微观粒子，每个光子都具有波粒二象性 C．光子本身所具有的能量取决于光子本身的频率 D．在光电效应中，用频率为v1的绿光照射某金属发生了光电效应，则改用频率为v2的红光照射该金属一定不发生光电效应 |
答案
答案：C
搜题请搜索小程序“爱下问搜题”
| 下列说法正确的是（ ） A．在光电效应中，光电子的最大初动能与入射光的频率成正比 B．光是高速运动的微观粒子，每个光子都具有波粒二象性 C．光子本身所具有的能量取决于光子本身的频率 D．在光电效应中，用频率为v1的绿光照射某金属发生了光电效应，则改用频率为v2的红光照射该金属一定不发生光电效应 |
答案：C
用方框中所给单词的适当形式填空，使短文通顺、正确、连贯（每个单词限用一次）。
Chana Goldstein, 16, amount saved: $ 1,000 I 小题2: saving for retirement at the age of 13. I set up my 小题3: website where I could get $2 an hour. So far, I have put $1,000 for retirement. Now I’m only in the tenth grade. I haven’t thought 小题4: what I will do when I retire. But I think the money will help me a lot. Grace Goldoni, 18, amount saved: $ 300,000 When I got my first money on my ninth birthday, I 小题5: it in a bank right away. I worked as a mother’s helper and then a babysitter. These jobs helped my savings keep 小题6: . I’m in college now and trying to get a new job. Most of the teenagers at my age 小题7: think about saving for retirement. They prefer(更喜欢) spending money. They should consider saving more seriously. Ryan Connelly, 20, amount saved: $26,000 It is 小题8: to see my money grow. Ever since I was 11, I have been putting money into three 小题9: saving accounts (储蓄账户). My mom always says I have saved what she and my dad had when they got married. When I retire, I’d like to live on my own 小题10: depending on others to take care of me. I don’t know what the right amount for retirement is, but it might be one million dollars. |