Springs

PK-1 ┊ 176 words ┊ ◄))
Springs








PK-1, 176 words, 3 minutes audio time.

Each book in this series focuses on a type of simple mechanism and examines how it is used to make different toys work. This book examines springs and uses simple language and labeled photographs to explain the scientific principles behind their use.

READ

Lib-html自然科学

Ramps and Wedges

2018-8-13 16:39:31

Lib-html自然科学

Screws, Nuts, and Bolts

2018-8-13 16:39:31