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## Homework Statement

P(average) for a speaker is 10 W. Gamma is 1.4 (ratio of specific heats), molar mass is 28.8 g/mol, air temperature is 50F, and pressure is 1atm. Find Pmax at 100

I have this equation that gives Intensity = (Pmax^2)/(2*Rho*v) where rho is density, and v is speed of sound through this air

## Homework Equations

All but one value has already been found:

Solved:

Rho = .001239 g/cm^3 = 1.239 kg/m^3

v = 338.28 m/s

I = 7.9577x10^(-5) W/m^2

(all reasonable values)

## The Attempt at a Solution

I'm just trying to solve for Pmax, very simple, but the units dont work out. So the equation becomes

Pmax = sqrt( 2 * I * Rho * v )

and the units for pressure become sqrt( J * kg / (m^4 * s^2) ) which is (square Joules) * (square kg) /( m^2 * s)

which doesn't make any sense to me, and the answer becomes 0.258 but intuitively this one doesnt seem reasonable, shouldn't the maximum pressure only be VERY slightly different than the regular pressure? Shouldn't the units be some kind of Force per area?