Q14 of 39 Page 300

Estimate the change in the density of water in ocean at a depth of 400 m below the surface. The density of water at the surface 1030 kg m-3 and the bulk modulus of water = 2 × 109 N m-2.

2 kg m-3

Given, density at surface,


bulk modulus of water,


Depth of water,


Pressure at this depth,


The bulk strain at depth h is




Now, density at depth h is


Here, V’ is compressed volume at depth h and is given by




Hence, change in density is


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