The Italian delegation of Science on Stage 2

The bottle of water with a sachet of mayonnaise

Abstract

The bottle of water with a sachet of mayonnaise is a disciplinary project based on the concepts and the experiments of hydrostatics done in the first two years of high school. The project begins with an amusing experiment which has quite a difficult solution: a sachet of mayonnaise is made to float within a plastic bottle that is filled up with water. The sachet descends when the bottle is squeezed and when the grip on the bottle is released the sachet once again floats. When asking the students to try to explain the operation we go down a curious and fun road of knowledge where all the concepts of hydrostatics are met (also through other simple experiments). At the end of the project the students manage to give an explanation on their own, based on the laws of hydrostatics. The series of small experiments made with simple and commonly used material brings Physics into daily life and brings the study of sciences into discussion.

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Description

Didactic objectives

• To introduce the students to the concept of pressure, Pascal's Principle and the Archimedes' Law.
• To make the students consider realistic cases from everyday life, resolving them through the use of various concepts of Physics.
• To get the students to apply theoretical concepts in practical situations.

Cultural objectives

• To demonstrate to the students that Physics is a part of daily life and that it can be a way of understanding non ordinary phenomenon.
• To make the students consider real-life situations that aren't easily solved, therefore stimulating confrontation, curiosity and problem-solving of situations in an age-group such as adolescents, which is a time of growth and of confrontation.
• To give Physics a fun, thought-provoking and stimulating image, preferring an understanding-based knowledge to a memory-based knowledge.

Methodology

• To make experimental Physics with easily-obtainable objects which are available to everyone, and which don't hide electronic mechanisms that often mask the phenomenon of Physics.
• to discuss, to compare ideas, take risks, and try out new approaches to solutions in order to interpret phenomena that is difficult to resolve.
• to review ideas that have already been looked at, at a later moment, after the introduction of a selection of concepts of Physics.
• to have fun whilst investigating unusual or strange phenomena.

More details about this activity are reported in this presentation.