▲ | trhway 6 days ago | |
When driving on highway, the wheels of other cars looks smudged. If i flicker my eyelids i see a snapshot of an other car's wheel like if it were not rotating, i.e. a strobe light like effect. That is ~1500rpm for human eye (and for us it is about 30ms for the signal to pass through the first stages of the visual cortex). Birds are several times faster (even if just for the much shorter physical path from eyes to the rest of the brain and of the related paths inside the brain). | ||
▲ | sandworm101 5 days ago | parent [-] | |
Actually, a semi truck tire is about 127" around. At 60mph, 1m per minute, that is more like 500rpm. For a car tire (80") that would be a little under 800rpm at 60mph. So you are seeing wheels spin aboit 10x per second, which is well within normal perception if you concentrate. Paint a dot on the tire and you would see it spinning around. Drone blades spin in the thousands, high thousands of rpms. |