Weight of core and dry soil, Q1, Problem set no. 1

why does the weight change when compacted? it should remain the same but the volume should change. Why should soil increase in weight when compressed? my understanding is that squishing soil will make water and air leave the soil making the soil lighter not heavier.

what is the difference between weight of core and dry soil, and weight of core? the question indicates that a double cylinder, drop hammer is used to obtain 750 cubic centimeters of soil. This I assume is the weight of the core.. so what then is the weight of the core and dry soil where does all this soil come from? from the tires of the truck?

thanks!

There are numerous points of confusion, which would be difficult to address here. Hence, I suggest that you attend one of 3 office hours that we have on Monday. Pls see TA office hours posted here in wiki. Sandra's office hour is 9-10 am on Monday

How does a soil change when compacted? Have a look at the example from your text (Chapter 4 section4.5 ) gone over in class (lecture 3) and consider the definition of bulk density.

In your class text (section 4.5 bulk density) there is a photo of a soil core used to sample soil for bulk density in the field. This metal core has a weight. The weight of the dry soil + core. Knowing both the weight of the soil + core, and the core alone you can calculate the weight of the dry soil. Agreed, drop by my office hour Monday 9-10 or Kiran 12-1 or Khalil 4-5 Monday; we can all show you a corer and explain how this works

i understand now that the "core" refers to the equipment used to make the measurement, in that case it is relatively straightforward.