How does light get from the sun to the earth? How does music get from the stage to the audience? They move the same way-----in waves!
Light and sound are forms of energy. All waves carry energy, but they may carry it differently. Light and sound travel through different kinds of matter. For example, light waves cannot move through walls, but sound waves can. That is why you can hear people talking in another room even though you cannot see them. The energy of some waves is destructive. An earthquake produces seismic waves.
Catch a wave. Ask a friend to stand a few feet away from you. Stretch a spring between you. Shake the spring to transfer energy to it. What happens? The spring bounces up and down in waves. When the waves reach your friend, they bounce back to you!
Light waves travel 300,000 kilometers per second! They can also travel through a vacuum. That is why light from the sun and distant stars can travel through space to the earth!
Useful Words and expressions;
1. destructive 破坏的
2. seismic地震的
3. vacuum真空
各式各样的店铺表达
雅思考试词汇每日累积四大名著
拜登中国行
常见的中式早餐
重压下的城市迷走症
汽车的词汇
雅思考试词汇各种鱼
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雅思考试词汇之麻将词汇
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早起看资讯
雅思考试词汇每日累积get的词组搭配
雅思考试词汇婚姻战争
雅思考试词汇可怜的猪猪
瓶装水与罐装牛奶
每日形容词汇
汽车部件词汇
地球仪词汇对照
雅思考试词汇遥控器
雅思考试词汇利比亚
雅思考试词汇酸辣土豆丝
常见乐器的表达
谢耳朵的关键词
雅思考试词汇如何表赞同
雅思考试词汇旋律之音
雅思考试词汇篮球词汇
太阳系天文词汇
雅思考试词汇地理专业词汇
雅思考试词汇每日记忆
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