# Two Identical Pistols Shot Simultaneously [closed]

Two identical pistols are shot at the same moment, one in Death Valley and the other the Schwarzwald Germany. Both of them are at targets 40 meters away. Which one hits its target earlier?

• I'm unsure if this is exactly on-topic for PSE. May 25 '19 at 5:50
• Pistols at 40 meters? They probably both missed. I guess I'd give the edge to the Death Valley cause 'Murica! May 25 '19 at 19:43
• I think this question is assumption heavy
May 26 '19 at 1:36

The target that gets hit earlier is

in Schwarzwald.

The elevation of Schwarzwald is 1,493m, while the elevation of Death Valley is -83m. Therefore the atmosphere is much thinner in Schwarzwald and offers less air resistance. The air resistance in Death Valley will cause the bullet to slow down more.

I'm pretty sure it

(This half-silly, half-serious answer is a bit heavy on the tag department, but since there are some quite interesting aspects involved, I thought I'd go ahead regardless.)

Let's assume that a pistol shot would take about 0.1 seconds to travel the 40 metres. Then, let's assume this value will be different in the two named places, and let's throw out that the difference might be as much as 10%. That amounts to a difference of about 10 milliseconds. Also, let's ignore any reasons as to why this would happen, even though Jay's answer seems very reasonable.

Now, the distance from Death Valley to Schwartzwald is about 9000 km along the surface of the Earth, or about 10% less than that if you go through the planet. In more applicable units, that would be about 0.03 light-seconds, which means that light would take 30 milliseconds to travel from one place to the other.

This tells us that the events of the bullets hitting their targets are well outside of each others light cones. This is critical, because it means the two events cannot be causally related in the relativistic sense, and therefore different observers can see the events happening in different orders.

Or in a more down-to-earth way: Even if the Death Valley bullet were 10% faster, anyone in Europe and Asia would still observe the Schwartzwald bullet hitting first.

This is, interestingly, the exact same reason why you don't want to play multiplayer first-person-shooter games on a server that's on another continent. Or turning it around once more: IRL has a high ping, too.

To put an opposing argument to the answer from @Jay:

Suppose at midday today in Death Valley the temperature is 38 Celsius and at the same moment (21:00) the temperature in Schwarzwald is 12 Celsius that's a 26 Celsius difference in temperature and consequently air density.

The table on this Wikipedia page suggests that there will be about 10% difference in air density, lower in Death Valley and consequently thinner, offering less resistance to the bullet.

So the bullet will reach the target earlier in:

Death Valley.

• Hm, that's an interesting detail.
– Jay
May 26 '19 at 9:21