Similar to calculating distance of photon traveling in space?

[adc22]

Homework Statement

Bullets of mass 1.53 gm are fired in parallel paths at speeds of 244.4 m/s through a hole 1.99 mm. How far from the hole must you be to detect a 1.77 cm in the beam of bullets

Homework Equations

The Attempt at a Solution

I feel as though some crucial information is missing (like a word between "1.77 cm" and "in the beam". Am I missing something here? Can someone just give me a clue on where exactly to start? My professor is not the best at explaining the concept behind the problem sets. Thanks in advance.

 

[adc22]

OP here.

So I have tried using Hubble's law, but is this the right approach? Should I be thinking about matter waves?

 

[Astronuc]

I imagine that 1.77 cm is the distance between bullets. Is this about resolving some spatial feature at a distance?

Presumably the 1.99 mm is the depth of the hole?

Are you doing something about the uncertainty principle by any chance?

 

[adc22]

I figured out the problem. I approached like a single-slit diffraction problem, and after calculating the wavelength of the bullets, calculated the distance to the "screen" to see half of the spread in the beam.

Thanks though. I sort of wish it had been a universe expansion problem!