如图是探究声音现象的实验装置，下列实验现象中正确的是（ ）
A．小球被弹开说明正在发声的音叉在振动
B．听到的声音越响，小球会被弹得越远
C．敲音叉的力越大，听到的音调就越高
D．用小球接触音叉的目的是为了放大音叉的振动效果，采用的方法叫转换法
A、小球被弹开说明正在发声的音叉在振动，此答案正确；
B、听到的声音越响，音叉的振幅越大，小球会被弹得越远，故正确；
C、敲音叉的力越大，音叉的振幅越大，听到声音的响度就越大，故此说法错误；
D、用小球接触音叉的目的是为了放大音叉的振动效果，采用的方法叫转换法，正确．
故选A、B、D
| 完形填空。 | ||||
| For me, Christmas always began in the middle of the cold, windy month of November. My sister Alice and I sat down in front of the fire and wrote a 1 to Father Christmas, telling him about all the presents we 2 . We carefully posted the letter to "Father Christmas, the North pole"… Christmas Eve came, The whole family helped to 3 the house, put up the Christmas tree and blow up the balloons. Then, in the afternoon, when Aunt Kate and my two cousins arrived, 4 was ready. Before we went to bed, we left some wine and meat for Father Christmas and then put our 5 at the end of our beds. We tried to keep 6 as long as possible to see Father Christmas, but the next thing we knew it was 7 Christmas morning! We couldn't wait to 8 the stocking. It was now full of all kinds of small present and sweets. Christmas morning was bright and sunny. After going to church, my cousin David and I went out into the garden to 9 our new present. Lunch was always late, but what a lunch! Delicious turkey with all the vegetables followed by fruits and ice creams. 10 lunch, Father, Mother and Aunt rested on the sofas in front of the Queen's speech on TV. We took out the toys, put on the funny paper hats, laughed at the jokes and played 11 . Then came the afternoon tea and a large 12 cake covered with snowmen. It didn't seem possible, 13 we still went on eating. By bedtime all of the children were very 14 . As soon as Mom 15 the light, we all fell into a deep sleep. | ||||
|