Mathematical and Physical Journal
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Problem G. 661. (February 2019)

G. 661. Three types of liquid, which do not mix with each other, are poured into a graduated cylinder: 100 g water of density 1000 kg/m\(\displaystyle {}^3\), 200 g oil of density 0.8 g/cm\(\displaystyle {}^3\), and mercury, such that the graduated cylinder of volume 400 cm\(\displaystyle {}^3\) and of height 40 cm is fully filled. How many grams of mercury was poured into the cylinder? At what height, measured from the bottom of the cylinder, are the boundary layers which separate the different liquids? (The density of mercury is \(\displaystyle 13\,600\) kg/m\(\displaystyle {}^3\).)

(3 pont)

Deadline expired on March 11, 2019.


Sorry, the solution is available only in Hungarian. Google translation

Megoldás. Egyenes mérőhengerbe három, egymással nem keveredő folyadékot öntünk: 1000 kg/m\(\displaystyle ^3\) sűrűségű 100 g vizet, 0,8 g/cm\(\displaystyle ^3\) sűrűségű 200 g olajat, és annyi higanyt, hogy tele legyen a 400 cm\(\displaystyle ^3\) térfogatú, 40 cm magas mérőhenger. Hány gramm higanyt öntöttünk a mérőhengerbe? Milyen magasságban helyezkednek el a folyadékokat egymástól elválasztó határrétegek a henger aljától számítva? (A higany sűrűsége \(\displaystyle 13\,600~\rm kg/m^3\).)


Statistics:

76 students sent a solution.
3 points:53 students.
2 points:12 students.
1 point:9 students.
0 point:2 students.

Problems in Physics of KöMaL, February 2019