UCSB Science Line
Sponge Spicules Nerve Cells Galaxy Abalone Shell Nickel Succinate X-ray Lens Lupine
UCSB Science Line
How it Works
Ask a Question
Search Topics
Our Scientists
Science Links
Contact Information
How can one calculate the amount of vaccum generated by a pump at different Mean Sea Level positions ( different locations) like in Mumbai and Delhi?
1. What will be the vaccum generated at 700 Mean Sea Level and at 600 Mean Sea Level?
Question Date: 2006-03-09
Answer 1:

Good question, the answer is rather complicated. I hope I have understood what you are asking...

First Mean Sea Level (MSL) is usually defined as the average height of the ocean at a particular location, averaged over a 19 year period. This occurs at an elevation of zero. As you probably know, as a general trend, increasing elevation corresponds to decreasing pressure.

Is your question possibly this: How low of a pressure can a vacuum pump generate at different elevations?

This is an interesting question. Lets think about the extremes. Say we have a mediocre vacuum pump that here in Santa Barbara can produces a vacuum in a small container of 10 Torr (0.014 times our ambient atmosphere, which is 735 Torr). The SAME PUMP, at a higher elevation of Mt. Everest where the pressure is only ~230 Torr does not have to work as hard to produce a vacuum of 10 Torr in the same small container. Therefore, it might, depending on the pump, produce a different (lower) vacuum such as 5 Torr.

So, in general, a vacuum pump is working to push gas (usually air) from one reservoir (a small closed container) to another (the atmosphere). This creates a pressure gradient that favors the gas moving back from our atmosphere into the vacuum container. The pump must work AGAINST this pressure gradient. At higher elevations, this gradient will be smaller, given the vacuum pressure (in the small containers) are the same. Therefore, it is likely that identical pumps could produce a lower vacuum at higher elevations. Think about even higher than Everest, SPACE! Here there already is a vacuum, so a pump doesn't have to work at all. But, it also doesnt have any gas to push around does it!

Read more about vacuums at

Hope this helps!

Click Here to return to the search form.

University of California, Santa Barbara Materials Research Laboratory National Science Foundation
This program is co-sponsored by the National Science Foundation and UCSB School-University Partnerships
Copyright © 2017 The Regents of the University of California,
All Rights Reserved.
UCSB Terms of Use