问题
选择题
如图1所示,小红做有关声现象的实验时,将一个正在发声的音叉贴近面颊,目的是为了 ( )
A.感受发声音叉的振动
B.体验发声音叉的温度
C.估算发声音叉的质量
D.判断声音的传播速度
答案
答案:A
当音叉发声时会振动,所以如果将正在发声的音叉贴近面颊,可以感觉到音叉的振动;
故选A.
如图1所示,小红做有关声现象的实验时,将一个正在发声的音叉贴近面颊,目的是为了 ( )
A.感受发声音叉的振动
B.体验发声音叉的温度
C.估算发声音叉的质量
D.判断声音的传播速度
答案:A
当音叉发声时会振动,所以如果将正在发声的音叉贴近面颊,可以感觉到音叉的振动;
故选A.
补全对话。 | |
Li: Hi, Wang Hai! It's a long time since we met last. 1 Wang: I've been to Kunming with my friends. Li: 2 Wang: Yes, of course. And we saw many kinds of flowersthere. 3 Li: Did you meet any foreign visitors? Wang: Yes, a lot. And I talked with some of them. Li: 4 Wang: They said we were very friendly. Li: 5 Wang: The delicious food and the places of interest.
| |
1. _____ 2. _____ 3. _____ 4. _____ 5. _____ |