Why a wheel turning at high speed appears to be turning the other way round?
If you take a basic wall clock and watch the minute hand, it moves very slowly, doing one rotation every 60 minutes. However, if you take a camera, and leave it to take a picture of the clock every hour, and watch those pictures like a movie, you'll think it doesn't move at all. Now take that cam…
The Short Answer
If you take a basic wall clock and watch the minute hand, it moves very slowly, doing one rotation every 60 minutes. However, if you take a camera, and leave it to take a picture of the clock every hour, and watch those pictures like a movie, you'll think it doesn't move at all. Now take that camera and make it take a picture every 61 minutes. Every picture it takes, the minute hand will have an extra minute to move, so will have gone slightly around the clock. Do it the other way around, and take a picture every 59 minutes. Even though it has moved forward, it looks like it has only moved back a little bit. Basically a similar thing is happening between your eye and the wheel at a significantly faster rate. Your eye is a bit trickier than just taking a photo on a regular basis, but the basic principles here are more or less the same.
Analysis
Key Concepts: Take, every, picture
This explanation focuses on take, every, picture and spans 159 words across 8 sentences. At 130% above the average Human Body explanation (69 words), this is one of the more thorough answers in this category, reflecting the complexity of the underlying question.
What This Answer Covers
The explanation opens with: “If you take a basic wall clock and watch the minute hand, it moves very slowly, doing one rotation every 60 minutes.” It then elaborates by presenting a contrasting perspective, ultimately building toward a complete picture across 8 connected points.
How This Compares in Human Body
Ranked #17 of 500 Human Body questions by answer depth (top 4%). This places it in the comprehensive tier — the top quarter of most thoroughly answered questions. Questions at this depth typically involve multi-faceted topics requiring nuanced explanation.
Frequently Asked Questions
Is there a simple explanation for why why a wheel turning at high speed appears to be turning the other way round?
If you take a basic wall clock and watch the minute hand, it moves very slowly, doing one rotation every 60 minutes. However, if you take a camera, and leave it to take a picture of the clock every hour, and watch those pictures like a movie, you'll…
How detailed is this explanation compared to similar Human Body questions?
This is one of the most thorough answer at 159 words, ranked #17 of 500 Human Body questions by depth. The key concepts covered are take, every, picture.
What approach does this answer take to explain why a wheel turning at high speed appears to be turning the ?
The explanation uses contrasting perspectives across 159 words. It is categorized under Human Body and addresses the question through 1 analytical lens.