這本書主要在描寫跟動能(movement)有關係的所有實驗,包括機器,地心引力…等跟動能有關係的現象及其相關實驗,適合9歲以上兒童閱讀,或是做為自然老師的補充教材。 More things move and everything that moves does so because of something called a force. What are forces and how do they work? Find out the answers to these questions and learn many fascinating facts about moting, as you perform simple and fun experiments with movement. |