Science Problems?

Question

HElp
?> I placed a hydrometer in water and half of it stickss out of the water A new liquid
(can be any) that is half the dense of water is tested how much of the hydro meter will stick out of the water
I know the answer is 1/4 in 3/4 is out but what is the formula!!!!

Answer 1

If The new liquid is only half as dense as water, the hydrometer will sink farther, so only 1/4 would be above the water and 3/4 would be below.
for a formula you can just set up a ratio of the amount above or below the liquid to the specific gravities of the liquids.

Answer 2

Water at 1g/cc with Hydrometer ½ submerged.
As the liquid is half the density of water at 0.5g/cc the hydrometer will be less submerged = ½ x 0.5 = ¼ unsubmerged. (3/4 in 1/4 out)

Answer 3

At first, V(1) is the volume below water, with density p(1).
V(1).p(1) is the force upward. If density p(2)=p(1)/2:
V(2).p(2)= V(2).p(1)/2
As V(2).p(2)= V(1).p(1), then
V(2).p(1)/2=V(1).p(1)
V(2)=V(1).p(1)/p(1)/2
V(2)= 2V(1), then length in water is twice, and it is completely into the water. 1/4 in water is a mistake.