第八课 Lesson Eight 1.谁能传播声音 Who can spread the sound 2.铃声一响，在学校各个地方都能听到。铃声是怎样传到我们的耳朵里的？ When the bell rings, it can be heard everywhere in the school. How does the bell ring in our ears? 3.准备两个纸杯、两个曲别针、风筝线、剪刀、图钉。 Prepare two paper cups, two paper clips and the wind Zheng line, scissors, thumbtack. 4.声音是怎样传播的？我们研究一下吧！ How is sound transmitted? Let's study it! 5.怎么研究呢？ How to study it? 6.这是我们小组的实验方案。 This is the experimental plan of our group. 7.实验方案 Experimental scheme 8.实验目的：证明空气能传播声音。 Objective: to prove that air can transmit sound. 9.实验器材：两支蜡烛、一盒火柴、大鼓、鼓槌。 Experimental equipment: two candles, a box of matches, drum, drumstick. 10.实验步骤 Experimental steps （1.）点燃蜡烛，一支放在鼓前面，一支放在较远处作为对比。 （1.） Light the candle, one in front of the drum and the other in the distance for comparison. （2.）敲鼓，观察现象。 （2.） Beat the drum and observe the phenomenon. 11.实验现象 Experimental phenomena 12.实验结论 empirical conclusion 13.我们的实验 Our experiment 14.用抽气机抽净罩内的空气… Exhaust the air in the hood with the air extractor 15.声音能在气体、液体固体中传播，传播方向是向着四面八方的。 Sound can be transmitted in gas, liquid and solid, and the direction of transmission is in all directions. 16.物体振动发声时，形成了声音的“波浪”，就像石子投入水形成的水波一样，一圈一圈地向周围扩散，并逐渐消失。 When an object vibrates and makes a sound, it forms a "wave" of sound, just like the water wave formed when a stone is thrown into the water, which spreads around and gradually disappears. 17.制作简易电话。 Make a simple phone. 18.怎样做效果好？ How to do it well? 19.换上铜线做电话线试试效果如何。 Put on copper wire to make a telephone line and try how it works. 20.在月球上，如果不借助任何工具，能否听到声音？为什么？ Can sound be heard on the moon without any tools? Why? |
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