Съдържание

IOM 2019, Експеримент — Задача 1. Exercise 1.1: Gas compressibility measurement

Оригинал на условието (PDF)Съобщи за грешка

Всички материали от IOM 2019

The 4th International Olympiad of Metropolises — Carbon Dioxide Solubility in Water

Recommendations Regarding the Experiment

There are two long exercises in the proposed experiment. Exercise 1.5 and exercise 2.1 in total may take more than three hours to complete. Consider this fact when allocating time and responsibilities to the participants during the experiment.

Условие

Part 1: Reference Points

Use a sticky tape to attach the long straightened PVC tube to the table. Attach the measuring tape next to the tube (see Fig. 1).

Five stages separated by dashed lines: a syringe attached to a long tube lying along a measuring tape, the other end in a water container; the tube being filled with water; water partly squeezed out; the water-filled end connected to a manometer showing 00.0; finally a 5-ml syringe with water pressing the air, the manometer showing 12.3 and the air column length between two water columns marked l. — Fig. 1. Preparation for measuring the dependence of length l of air column in the tube versus additional pressure

Using a 20-ml syringe, fill the tube fully with water by lowering the open end of the tube into a cold water box. After that, squeeze out a part of water from the tube so that completely filled is only a part of the tube, which is close to a tube end. Connect this end of the tube to the manometer. Disconnect the 20-ml syringe from the tube. Fill with water the 5-ml syringe and attach it to the other end of the tube, where the larger syringe was attached and where there is no water. Press the syringe piston to create additional pressure in the tube. Experimentally obtain the relationship between the air column length $l$ inside the tube and additional pressure $\Delta p$ in it. Enter the measurement results in the table. Get at least 7 experimental points in the whole range of possible pressures.

In a few words in English (or Russian), or by means of symbolic drawings, explain the main reason why the edge of the water column that is closer to the manometer moves when the pressure changes. In this connection note the description of the manometer.

Отговори

Решение

Answer Sheet

Exercise 1.1

$\Delta p$ , mmHg	$l_1$ , cm	$l_2$ , cm	$l$ , cm
-5.2	0.0	97.6	97.6
27.7	5.0	98.1	93.1
61.8	10.0	98.6	88.6
102.8	15.0	99.1	84.1
147	20.0	99.55	79.55
196	25.0	100.2	75.2
250.3	30.0	100.8	70.8

Briefly explain why the edge of water column in the tube near the manometer moves when the pressure is changed?

compression of air in the manometer inlet

(and changing in cross-section area of the tube)

Оригинал в Архива: phys-task-prak-iom-2019-en.pdf · официални решения: phys-solution-prak-iom-2019-en.pdf