Q1: The total weight of a pycnometer with water and oven dried soil 20 (g) is 1600 g. The pycnometer filled with water alone weighs 1500 g. The specific gravity of the soil, is

ANS:C - 2.0

Let,

Empty weight of pycnometer = W1.
Empty weight of pycnometer + dry soil = W2.
Empty weight of pycnometer + dry soil + water = W3.
Empty weight of pycnometer + water = W4.

W1=p.
W2=p+200.
W3=1600.
W4=1500.
G= (W2-W1)/(W3-W4) = P+200-P / 1600-1500.
= 2.
Dry Weight must be 200g. Let,
The empty weight of pycnometer = W1.
The empty weight of pycnometer + dry soil = W2.
The empty weight of pycnometer + dry soil + water = W3.
The empty weight of pycnometer + water = W4.

W1=p.
W2=p+200.
W3=1600.
W4=1500.

G = (W2-ww)/[(W4-W1)-(W3-W2)].
= (P+200-P)/[(1500-P)-(1600-P-200)].
= 200/[1500-P-1600+P+200] = 200/100 = 2. The formula for finding G by pycnometer method is---> Ws/Ws-W3-W4.

Where W3 = wt of pycnometer + wt of soil + wt of water and W4 = wt of pycnometer+wt of water.