When I was about 6 or so I was fascinated by the fact that when you drop a coin in a fast moving car or train, how it moves through the air at the ame speed, not ending up moving backwards (falling at the point it had been dropped, not straight down). It took a while to realise that this was because the air inside the vehicle was moving too. Even if you open a window.
A childhood belief about physics

others believed things like this
- When I was about 4 and I saw the clouds moving sideways, I thought that Earth was moving closer to the Sun— Helen
- I used to believe that when I saw the clouds moving in the sky, that it was actually the earth moving. — Megan Gilbert
- I believed I could tap dance by moving my feet real fast. — Aussie
- I used to believe when it thundered that god was moving his furniture around.— Debra Mcewan
- When I was a kid, I used to believe that it would thunder when G-D was moving furniture in the sky.Anon
- I used to believe that when it thundered it was God moving the furniture around up in heaven!— Clare N.I.