Percentage Decrease in Specific Volume using Bulk Modulus from Table

In summary, the conversation discusses the use of Table 2.1 to determine the percentage decrease in specific volume of water in a hydraulic press when subjected to different pressures. The attempt at a solution involves using the average value of E at the given pressures, but the back of the book gives a different solution.
  • #1
lizzyb
168
0
Homework Statement

"Water in a hydraulic press is subjected to a pressure of 4500 psia at 68 F. If the initial pressure is 15 psia, approximately what will be the percentage decrease in specific volume. Use Table 2.1 (below)."

Homework Equations



http://img86.imageshack.us/img86/7606/scanx200908280001.jpg

http://img198.imageshack.us/img198/2330/scanx200908280002.jpg

The Attempt at a Solution



It seems easy enough:

http://img38.imageshack.us/img38/6264/scanx200908280003.jpg

but the back of the book gives 1.34%; what is wrong with my solution?
thx
 
Last edited by a moderator:
Physics news on Phys.org
  • #2
I came up with the correct solution taking the average value of E at psia = 15 and 4500 (E = [348000 + 320000]/2); how would I justify this?
 
  • #3


Your solution is correct. The back of the book may have a typo or have used a different table or method for calculation. It is always important to double check your work and use reliable sources for reference. In this case, your solution is supported by the provided table and equations.
 

Related to Percentage Decrease in Specific Volume using Bulk Modulus from Table

1. What is a percentage decrease in specific volume?

Percentage decrease in specific volume refers to the change in volume of a material when subjected to a compressive force. It is expressed as a percentage of the original volume.

2. How is bulk modulus used to calculate a percentage decrease in specific volume?

Bulk modulus is a measure of a material's resistance to compression. It is used in the formula for calculating percentage decrease in specific volume, which is (change in bulk modulus/original bulk modulus) * 100.

3. What is the significance of using Table for calculating percentage decrease in specific volume?

The Table contains the bulk modulus values for different materials. By using the specific bulk modulus value for a material, we can accurately calculate the percentage decrease in specific volume for that material.

4. Is it necessary to know the original and final volumes to calculate percentage decrease in specific volume?

Yes, the formula for calculating percentage decrease in specific volume requires the change in bulk modulus as well as the original bulk modulus. Therefore, the original and final volumes must be known.

5. Can percentage decrease in specific volume be negative?

Yes, percentage decrease in specific volume can be negative if there is an increase in volume instead of a decrease. This can occur if the material is subjected to a tensile force instead of a compressive force.

Similar threads

Calculating change in volume (bulk modulus)
    • Introductory Physics Homework Help
Replies
1
Views
4K
How Do I Calculate Bulk Modulus from DFT Data for Solid Carbon Dioxide?
    • Advanced Physics Homework Help
Replies
1
Views
5K

Hot Threads

Recent Insights

Back
Top