Calculation of atmospheric presure

[Derek1997]

Homework Statement

Taking atmospheric pressure at sea level to be 1x10^5 pa CPa and the density of air at sea level to be
about 1.2kg/m^3,estimate the atmospheric pressure in London 550m above sea level. For this calculation, it is easiest to assume that air density doesn’t change with height – briefly discuss
the validity of this assumption

Homework Equations

patm= rho g h

The Attempt at a Solution

Well, I did p=pgh- 1.2x9.8x550 and substracted the answer by the atmosperhic pressure of the sea to get the answer? Am I right?

 

[Bystander]

Am I right?

Don't know, you haven't stated your result. It's certainly one way to "estimate" atmospheric pressure in London.

 

[Derek1997]

Don't know, you haven't stated your result. It's certainly one way to "estimate" atmospheric pressure in London.

Well alright thanks for reply.. here the results i got above
so for p atmospheric i got- 1.2kg/m^3x9.8m/s^2x 550m= 6648pa then i substractfrom the very given pressure that is 1x10^5pa-6648pa= 93352pa pressure of london?

 

[Bystander]

1x10^5pa-6648pa= 93352pa pressure of london?

You might want, in addition, to pay attention to significant figures.

 

[Derek1997]

You might want, in addition, to pay attention to significant figures.

you mean i convert to kpa?

 

[Bystander]

to significant figures.

Not units --- significant figures.

 

[Derek1997]

I don't understand. 93352pa= 92.5kpa?

 

[Bystander]

Yes. I'll re-emphasize the "might," I've no idea how picky your instructor "might" be.

 

[Derek1997]

Oh ok, thanks i gave u a like.

 

[Bystander]