Step-by-step tutorial
Step 1
Can we move fast enough that we can knock out the bottom penny without bringing down the whole tower? Would the friction of the coins work for us or against us? Let's find out.
Step 2
We knew that we wanted to remove just one coin, so that meant that we had to hold the knife as flat against the table as possible.
Step 3
With full confidence that she had this on her very first try, Madeleine gave it a shot. One.... two.... ("Move your hand out of the way, baby...")
Final result!
...Three! She was right! She so had this. Her "force" was certainly enough to make friction work for her... the other objects remained at rest! Hmm... now I wonder how this would turn out with a shorter stack? Or a taller one?....
