A penny dropped from the Empire State Building would kill someone
Scientific Reality
A penny reaches terminal velocity of ~40 km/h — enough to sting, not to kill.
Historical & Cultural Context
Everyday intuition and simplified classroom explanations hardened into "common knowledge" long before careful measurement caught up. As a question of physics, "A penny dropped from the Empire State Building would kill someone" slotted neatly into what people already expected to be true, which is exactly why it went unquestioned for so long.
Because it sounded reasonable and was taught early, few adults ever revisited it. It was not until 2004 that the record was set straight — a penny reaches terminal velocity of ~40 km/h — enough to sting, not to kill. The correction came from MythBusters Season 3 (2004); Kurtus, R. — School for Champions (Physics), yet the original myth still lingers in everyday conversation.
A Different Lens
Intuition is a terrible instrument for reality. This myth persists because the truth is counterintuitive — and being wrong felt perfectly logical. It survives not because it is convincing but because it is so rarely challenged out loud. Strip away the folklore and the sharper truth comes into focus — start with a single fact: penny mass: 2.5 g; drag coefficient: ~1.12 (flat plate). Seen this way, the myth is less a mistake to mock than a case study in how belief outruns evidence.
Deep Dive
A penny is an irregular, flat object with very low mass and significant aerodynamic drag. In free fall, it tumbles and wobbles rather than falling straight, reaching terminal velocity of ~35–45 km/h (22–28 mph). This is about the force of a strong flick. MythBusters (2004) confirmed this experimentally — no injuries. A falling ball bearing would be a different story.
- Penny mass: 2.5 g; drag coefficient: ~1.12 (flat plate)
- Terminal velocity: ~35–45 km/h due to aerodynamic drag
- MythBusters (2004): penny fired at skin — equivalent to a strong flick
- A steel ball bearing (~15g) falls much faster and would cause serious injury
Visualization
Terminal Velocity Comparison — Penny vs. Spherical Objects
Physics diagram comparing free-fall terminal velocities of common objects dropped from height: a penny (~40 km/h), a golf ball (~145 km/h), and a baseball (~160 km/h). Mass, drag coefficient, and cross-sectional area determine terminal velocity.
Verified Sources & Peer-Reviewed References
MythBusters Season 3 — Penny Drop
Discovery Channel / Beyond Productions·2004Aerodynamics of Tumbling Objects
Journal of Fluid Mechanics·2010Physics of Free Fall and Air Resistance
American Journal of Physics·2003Terminal Velocity Measurements
Physics Teacher·2012
All sources are peer-reviewed or from accredited space agencies. Dark Myths does not fabricate or misrepresent scientific findings.