This video explores the myth that a penny dropped from the Empire State Building can be lethal. The host, along with Adam Savage, a former MythBuster, conduct experiments to test this claim. They drop pennies from a helicopter and measure their terminal velocity, which is found to be around 80 km/h, not enough to cause harm. The video also delves into the concept of terminal velocity and how it's affected by air resistance, explaining why objects like hailstones can be deadly due to their larger size and higher terminal velocity.
Additionally, the video covers other topics such as:
* The terminal velocity of different objects, including raindrops and bullets
* The concept of drag coefficient and how it affects the aerodynamics of objects
* The dangers of falling objects in civilian life, including construction tools, rocks, and tree branches
* The use of kinetic projectiles in warfare, including flechettes and lazy dogs
The video concludes by promoting the online learning platform Brilliant, which offers interactive STEM courses and problem-solving exercises.
Here are the key facts extracted from the text:
1. A penny weighs around 2.5 grams.
2. The weight of a bullet is roughly 4-8 times the weight of a penny.
3. A penny dropped from the Empire State Building (443 meters) would accelerate to over 300 km/h by the time it hits the ground.
4. The terminal velocity of a penny is at most about 80 km/h.
5. The terminal velocity of a raindrop is around 25 km/h.
6. Hailstones can reach terminal velocities of over 200 km/h.
7. The terminal velocity of a falling object depends on its weight and air resistance.
8. The drag coefficient of an object affects its terminal velocity.
9. A bullet fired straight up will fall back down at a slower speed due to air resistance.
10. The lower limit of energy required to fracture a human skull is around 68 joules.
11. Objects that weigh more than a few hundred grams and are aerodynamic can be deadly when falling at terminal velocity.
12. Nearly 700 Americans die each year from being struck by a falling object.
13. The Empire State Building is 443 meters tall.
14. Felix Baumgartner jumped from a helium balloon 39 kilometers above sea level in 2012 and reached a terminal velocity of over 1300 km/h.
15. The air density at an altitude of 39 kilometers is 60 times less dense than at sea level.
16. The terminal velocity of a person is around 200 km/h.
17. A lacrosse ball and a person can have the same terminal velocity if their weight-to-air-resistance ratio is the same.
18. The wind tunnel used in the experiment had a gradient of wind speeds from around 100 km/h at the bottom to 25 km/h at the top.
19. The drag coefficient of a sphere is 0.5.
20. The drag coefficient of a modern bullet is between 0.1 and 0.3.