The myth has persisted for years: dropping a penny from the top of the Empire State Building could kill someone below. But is there any truth to this notion? It's a question that merges urban legend with physics, legality, and public safety. In this article, we'll unpack the supposedly lethal penny's science, explore real-life experiments and studies, and discuss the legal and safety considerations of dropping any object from such heights. As we delve into this topic, we'll uncover what happens if someone drops a penny off the Empire State Building.
Understanding the Physics
The perception that a penny dropped from the Empire State Building could be lethal is based on the idea that an object falling from such a height would accumulate extraordinary speed, making it deadly upon impact. However, this idea doesn't hold up when we consider the principles of physics, specifically the interplay between gravity, terminal velocity, and the specific characteristics of the penny itself.
When any object is dropped from a height, it initially starts with a speed of zero, then accelerates downwards due to the force of gravity. Without air resistance, all objects, irrespective of their mass, would continue accelerating at around 9.8 m/s² until they hit the ground.
However, our world is filled with air, which drastically changes the picture. The penny, as it falls, collides with air molecules. These collisions create a drag force that opposes the penny's downward motion. As the penny picks up speed, the drag force increases until it equals the force of gravity acting on the penny. At this point, the penny no longer accelerates and continues to fall at a constant speed called terminal velocity.
The terminal velocity of an object depends on its shape and mass. For a small, flat object like a penny, the terminal velocity is quite low due to the relatively large surface area encountering air resistance compared to its weight. Estimates put the terminal velocity of a penny at around 50 miles per hour.
Therefore, if you were to drop a penny from the Empire State Building (or any other height beyond which it could reach its terminal velocity), it would hit the ground at its terminal velocity, not at speed proportional to the height it was dropped from. At around 50 miles per hour, it might sting, but it wouldn't cause serious injury.
Additionally, the design of skyscrapers often causes updrafts, which could cause the penny to be blown off course, potentially even causing it to end up higher than the starting point.
In conclusion, dropping a penny from the Empire State Building is unlikely to cause damage due to its terminal velocity. However, it's still not advised because it can be a nuisance or distraction, which can be hazardous in a bustling city like New York.
The Myth: Can a Penny Kill?
Contrary to popular urban legend, a penny falling from the Empire State Building or any other skyscraper won't kill a pedestrian on the ground. This myth has been propagated through various means, from casual conversations to being stated as fact in movies and television shows.
In reality, physics doesn't support this claim. When an object falls through the atmosphere, two primary forces are acting on it: gravity, which pulls it downward, and air resistance, which opposes its downward motion. For a penny, its flat, thin, and lightweight characteristics contribute to a low terminal velocity — the highest speed it can achieve when falling. As mentioned, this terminal velocity is estimated to be around 50 miles per hour.
A penny might sting if it hit you at this speed, but it would hardly be lethal. Several physicists and science TV shows like MythBusters have debunked this myth through calculations and practical experiments. Their findings demonstrate that even after falling from a great height like the Empire State Building, the penny would not have enough energy to inflict severe harm or cause death.
However, it's important to note that while the penny itself isn't dangerous, dropping any object from a tall building can be. Even a harmless penny can startle or distract someone, potentially leading to hazardous situations in a busy city environment.
In summary, while a penny dropped from the Empire State Building won't kill you, keeping all objects, no matter how small or seemingly harmless, from free-falling off tall structures is best. Not because of the potential physical harm they could inflict but due to the potential for distraction and surprise they could cause in the bustling city life below.
Real-life Experiments and Studies
Over the years, numerous individuals and organizations have tested the lethal penny myth in real-life scenarios to debunk it. Here are a few notable experiments and studies conducted:
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MythBusters: In one of their episodes, the MythBusters team recreated the scenario by dropping a penny from a height equivalent to that of the Empire State Building. Using a wind tunnel and a high-speed camera, they determined that a penny reaches its terminal velocity of about 50 miles per hour. When they fired a penny at this speed into a skull analog, it bounced off, debunking the myth that a penny dropped from a great height could kill a pedestrian.
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Scientific American: Similarly, Scientific American conducted a theoretical study. They, too, concluded that the terminal velocity of a penny falling edge-first (its most likely orientation while falling) is about 50 miles per hour and that the energy it carries wouldn't be sufficient to cause severe injury or death.
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Purdue University Study: Physicist Louis Bloomfield from the University of Virginia experimented and found that the maximum speed a penny could reach was 30 to 50 miles per hour - not nearly fast enough to kill or seriously injure anyone. Bloomfield further explained that the penny's shape and mass prevent it from becoming a deadly projectile.
Each of these experiments concluded that contrary to popular belief, a penny dropped from the height of the Empire State Building is not deadly. While it's not advised (or legal) to throw objects from tall buildings due to potential unintended consequences, fears of lethal pennies can be laid to rest.
What Would Actually Happen?
So what would happen if someone dropped a penny from the top of the Empire State Building? Simply put, it would fall to the ground, but it wouldn't cause the catastrophic damage popular myth might have you believe.
As we've established, a penny can only reach a terminal velocity of around 50 miles per hour due to its shape and mass. When it eventually hits the ground, or perhaps an unfortunate passerby, it wouldn't travel fast enough to cause serious harm. At most, getting hit by such a penny might feel like being flicked, not pleasant by any means, but far from deadly.
Additionally, the urban environment surrounding the Empire State Building would influence the coin's descent. The wind could carry the penny off course, and the various skyscrapers could act as barriers.
It's also worth noting that the Empire State Building observation decks are enclosed by tall fences specifically designed to prevent objects from being dropped.
So, while it's an intriguing thought experiment, the reality is relatively mundane and much safer. The danger of a penny dropped from the Empire State Building is an enduring urban myth.
Legal and Safety Considerations
A penny dropped from the Empire State Building can cause serious harm, so it's crucial to highlight the importance of safety and legality. Regardless of the physics involved, throwing objects off tall buildings is dangerous and illegal.
While a penny may not have the capacity to kill, it could startle pedestrians, possibly causing accidents or triggering panic. Objects with more mass or aerodynamic shape can become lethal projectiles when dropped from significant heights.
Legally, dropping objects from tall buildings like the Empire State Building is considered reckless endangerment and is punishable by law. The exact consequences can vary, but they may include hefty fines, imprisonment, or both. This rule isn't limited to just coins but applies to any objects that could harm individuals or property.
Moreover, buildings like the Empire State Building have strict safety regulations, including protective barriers around observation decks to prevent such incidents. Security ensures visitors enjoy stunning views without harming the people and structures below.
