Force and motion
Force and Motion
Peek-a-Boo vs Hand-Waver System Diagrams
PLEASE NOTE: In this video the word parallel refers to the *arrangement *of the pop-ups, not the type of pop-up (as in “parallel-fold”). For example, in the stair-step construction, two parallel-fold pop-ups are in series, while the Monster and **Mouth **each features two angle-folds in parallel. It’s unfortunate that the same word, “parallel,” has these two separate meanings!