Does the weight change from dry to wet dirt increase linearly or exponentially?

Question

Does the weight change from dry dirt to wet dirt change linearly or exponentially as the dirt expands as a result of being soaked from a water source? Is the sum of the weight of dirt + weight of water equal to both sources when they are separate or is it more than the two separate weights when combined?

Answer 1

Linearly - Think if you add 1 pound of water every hour. You start with 10 pounds of dry dirt. After 1 hour you have 10 pounds of dirt plus 1 pound of water. After 2 hours, you have 10 pounds of dirt and 2 pounds of water, etc. Plot that on a graph and it will be a straight line.

Answer 2

Lets see now ... when two things are put together, is more weight (mass) produced?

Think of putting a 1 pound weight and a 2 pound weight together.  Will they be less, more, or equal to 3 pounds?

Does it matter if it is 1 pound of water and 2 pounds of dirt?