问题
单项选择题
若用衍射光栅准确测定一单色可见光的波长,在下列各种光栅常数的光栅中选择 ( )最好。
A.1.0×10-1mm
B.5.0×10-1mm
C.1.0×10-2mm
D.1.0×10-3mm
答案
参考答案:D
解析:光栅常数越小,衍射效果越好
若用衍射光栅准确测定一单色可见光的波长,在下列各种光栅常数的光栅中选择 ( )最好。
A.1.0×10-1mm
B.5.0×10-1mm
C.1.0×10-2mm
D.1.0×10-3mm
参考答案:D
解析:光栅常数越小,衍射效果越好
选择方框中适当的单词或短语填空。(每词限用一次) | |
2. If you have anything in trouble, you can ________ 110 ________. 3. I'll _______ to look for my lost watch. 4. My mother is ill. I have to ________ her at home today. 5. We often ________ that book after school. 6. My home is ________ my school. So I go to school by bus. 7. ________! A car may hit you. 8. — How can I ________ the bus stop? — Turn left and walk on. It's on your left. 9. — What about ________ shopping with me? — Good idea. 10. They are singing and dancing at the party _______. Let's go and have a look. |