# Homework Help: Homework question

1. Feb 25, 2006

### xyz123

if atmospheric pressure is 730mm of mercury, what is this in pascals..?

based on my study guide 1atm = pgh

= 13,590 kg/m(cube) * 9.807 N/kg * 0.76m

= 101,300Pa

do i calculate it as such :

= 13,590 kg/m(cube) * 9.807 N/kg * 0.73m...?

i even tried by g = 10N/kg instead of 9.807 (if less accuracy is needed)...
but my answer still does not tally..? i'll be able to find the pressure in atmospheres and millibars once i obtain the calculating method to the first problem....pls help !

Last edited: Feb 25, 2006
2. Feb 25, 2006

### Hootenanny

Staff Emeritus
There are 133.322 pascals per mm of mercury

3. Feb 25, 2006

### xyz123

thx you so very much for the quick reply...by multiplying 133.322 pascals to 730mm (mercury) i obtained the answer 97,325.06 pascals which very close to the method i first used in the previous post (97,292.3049 pascals).
why does my study guide state 96,000 pascals as the answer ? i'm so sorry but i have no tutor and i study by myself (very new to physics)...thx you!

4. Feb 25, 2006

### Hootenanny

Staff Emeritus
I dont quite know

5. Feb 25, 2006

### xyz123

ok thx so much though...last question...the method that i used (first post)..is it also considered a correct way of finding the answer..? are you a moderator..? should i leave this post as it is hoping someone else might be able to answer it or should i close this post once you reply to it (the 'last question')..? sorry for the trouble...thx!

6. Feb 25, 2006

### Hootenanny

Staff Emeritus
Im not a moderator, it is a good idea to leave the post open as people have different specialities and are more qualified than me to answer your question, after all I am mearly a student! Your method looks fine and as the two answer are in close agreement I would expect them to be right. Check back soon to see if anyone else has added to your post.

7. Feb 25, 2006

### xyz123

Forces & Pressure (Homework Question)

thank you so much ! i appreciate your assistance.

can anyone pls help me figure out why my study guide states a different answer. thx !

Last edited: Feb 25, 2006