If a tire is punctured (or if any container full of air is holed) the air starts to leak out. Consider a small area A of the wall of the container. Show that the number of molecules striking this surface in a time interval Δt is(adsbygoogle = window.adsbygoogle || []).push({});

pAΔt/2m<Vx>

p is the pressure

m is the average mass of the air molecule

<Vx> is the average x-velocity of the molecules

Assume collisions with the wall are elastic

By having elastic collisions, the KE is conserved and none of the KE is transfered in any other form

In class, we showed that p= -ΔP/Δt

where P is the average molecular momentum

pressure (p)=F/A

therefore -ΔP/Δt=F/A

F=ma => -ΔP/Δt=(ma)/A

that is where I have gotten so far. Not sure if I am doing this right or where to go from here

Please help!

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Calculating Molecules in a punctured tire

**Physics Forums | Science Articles, Homework Help, Discussion**