What is the Pressure of Falling Sand on a Sticky Surface?

[dmark312]

Homework Statement

Grains of sand of mass 2.90x10^-3 g each, fall from a height of 0.5 m on a sticky surface at a rate of 45 grains per second per cm^2. What pressure does this shower of sand exert on the surface, assuming that air resistance can be neglected?

Homework Equations

p=F/A=mv^2(N/V)

The Attempt at a Solution

I don't know where to start. Anyone care to point me in the right direction?

 

[m.e.t.a.]

You can work out the velocity with which every grain of sand lands. You also know what total mass of sand falls per second. Your force, F, is equal to the force required to accelerate that certain mass of sand by that certain velocity in one second.

 

[Redbelly98]

Welcome to PF

P = F / A is definitely useful here.

Also of use is

F = Δp / Δt

where little p is momentum (not pressure). You'll need to figure out the change in momentum, for the total of all grains of sand that hit a square cm of the surface, in 1 second.