Real-world Physics:
* Pendulum Motion: Spider-Man's swinging is similar to a pendulum. The speed at the bottom of the swing depends on the length of the web and the height from which he starts.
* Air Resistance: Air resistance would play a significant role, slowing Spider-Man down.
* Strength: His superhuman strength allows him to launch himself into the swing with great force.
Comic Book Feats:
* Speed of Sound: Spider-Man has been depicted moving at speeds close to or exceeding the speed of sound.
* Across the City: He routinely swings across large distances in a short period of time.
* Avoiding Attacks: His fast reflexes allow him to dodge attacks from incredibly fast opponents.
Estimates:
* Based on pendulum motion: Assuming a web length of 100 feet and a starting height of 50 feet, a theoretical maximum speed could be around 60 mph.
* Comic book feats: Some sources estimate his top speed at Mach 1 (767 mph).
Important Considerations:
* Inconsistent Depiction: Different writers and artists often have different ideas about Spider-Man's abilities, resulting in varying speed estimates.
* Artistic License: Comic books often prioritize visual spectacle over realistic physics.
* Storytelling Purpose: Spider-Man's speed often serves the story's needs, whether it's to escape danger, chase a villain, or simply impress the reader.
Conclusion:
While there's no definitive answer, Spider-Man is depicted as being incredibly fast, likely exceeding the speed of sound in some instances. His swinging speed depends on factors like web length, starting height, and the specific story being told. However, his speed is always impressive and crucial to his abilities as a superhero.