When the snow melted that spring, every stream became an angry river that raced down the mountains tearing up trees and bringing destruction.

VOA: special.2009.06.06

The spring is getting squashed because you are pushing down and the floor is pushing up.

弹簧现在被压缩了,因为你在往下压,地面在往上推

耶鲁公开课 - 基础物理课程节选

The spring is getting squashed because you are pushing down and the floor is pushing up.

弹簧现在被压缩了,因为你在往下压,地面在往上推

耶鲁公开课 - 基础物理课程节选