(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Molecules of hydrogen, each has mass of 3.3 x 10^{-27}kg, move with speed 1.6 kms^{-1}hit a wall at angle π/3 rad to the normal. If there are 2.0 x 10^{20}molecules s^{-1}hit the area of 1.2 x 10^{-4}m^{2}, find:

a. the average normal force on the wall if all the molecules are absorbed by the wall

b. the average normal force on the wall if all the molecules are reflected

c. pressure exerted by case (a) and (b)

2. Relevant equations

P = F/A

p = mv (momentum)

Δp = F.Δt

3. The attempt at a solution

Δp = F.Δt

Nmv = F cos (π/3) . t ; N = number of molecules

F = (N/t . m . v) / cos π/3

What is the difference when the molecules are absorbed and when reflected? Thanks

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# Homework Help: Force and pressure done by molecules

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