Topic: How does the thermometer work?

Target group

4th‑grade students of elementary school

Core curriculum

4th grade of elementary school

III. Weather, weather ingredients, weather observation. Student:

1. lists the weather components and gives the names of the instruments used to measure them (air temperature, cloudiness, precipitation and atmospheric sediments, atmospheric pressure, wind direction);

2. reads the values of the measurement of weather components using appropriate units;

3. conducts observations of weather components, records and analyzes their results and sees dependencies.

General aim of education

Students explain how to properly read the air temperature.

Key competences

• communication in foreign languages;

• digital competence;

• learning to learn.

Criteria for success
The student will learn:

• explain how the liquid thermometer works;

• properly read the temperature;

• describe the scale of Celsius.

Methods/techniques

• activating

  • discussion.

• expository

  • talk.

• exposing

  • film.

• programmed

  • with computer;

  • with e‑textbook.

• practical

  • exercices concerned.

Forms of work

• individual activity;

• activity in pairs;

• activity in groups;

• collective activity.

Teaching aids

• e‑textbook;

• notebook and crayons/felt‑tip pens;

• interactive whiteboard, tablets/computers;

• items and substances needed to perform „Experiment 1”: a small glass bottle (e.g., fruit juice), dark food coloring, plasticine, a plastic drinking straw, two bowls, cold and hot water.

Lesson plan overview

Before classes

• Students get acquainted with the content of the abstract. They prepare to work on the lesson in such a way to be able to summarize the material read in their own words and solve the tasks themselves.

Introduction

• The teacher, referring to previous lessons, asks students how the volume of liquid changes under the influence of temperature.

• The teacher explains the aim of the lesson and together with students determines the success criteria to be achieved.

Realization

• The teacher instructs students to read the fragment „How do we measure the temperature?” And become acquainted with the construction of a liquid thermometer.

• The teacher asks students to exchange substances used in liquid thermometers, and then explains why these substances are useful for constructing this type of thermometers.

• The students perform Experiment 1, write in notebooks observations and conclusions.

• The teacher announces a movie. He instructs his pupils to write a research question and a hypothesis in the form provided in the abstract. Then he plays the video and the students note their observations and conclusions. The teacher points the person who shares his insights and explains the reasonableness of the conclusions noted.

• The teacher asks students to give them examples of using thermometers. Writes all ideas on the board. Then he displays the pictures from „Gallery 1” and asks students about the possibility of using the thermometers depicted in the photographs..

Summary

• The teacher asks students to carry out the recommended interactive exercise themselves.

Homework

• Listen to the abstract recording at home. Pay attention to pronunciation, accent and intonation. Learn to pronounce the words learned during the lesson.

The following terms and recordings will be used during this lesson

Terms

Texts and recordings

How does the thermometer work?

For „warm” we consider objects that are warmer than our skin, and for „cold” – cooler than it. Comparing the temperature of different objects to the warmth of our body is not very accurate. Therefore, to precisely determine the temperature, we use special devices – thermometers.
Thermometers should be constructed so that everyone will measure the temperature on the same scale – as in the case of mass, in different countries, we measure in kilograms. The most commonly used method of temperature measurement is to determine it according to Celsius, named after its creator, Anders Celsius. As zero degrees Celsius – which is written abbreviated as 0°C – the freezing point of the water was assumed. The boiling point of water is one hundred degrees Celsius (100°C). Between these points on the scale, after dividing it into 100 equal parts, the size of one degree Celsius is determined. Values lower than the water freezing temperature are called negative and have a minus before the number, e.g. -10°C. Higher values are called positive, we usually write them without any characters, but you can use the plus entry, eg +30°C.

Different thermometers are used to measure the temperature of different substances. The air temperature is measured by a window thermometer. It is important to attach it in the shade. Exposing the thermometer to the full sun will cause it to heat up from its rays and the reading will not be accurate. Thermometers are also used in the kitchen – you can measure the temperature of the food being prepared, eg roasts in the oven. The temperature of the human body is measured with a medical thermometer, which shows a narrow temperature range. Researchers also use special thermometers to measure very high temperatures, e.g. +1200°C or low temperatures, e.g. -100°C.

• A thermometer is used for precise temperature measurement.

• The operation of liquid thermometers is based on the thermal expansion of objects.

• The Celsius scale was created by dividing into 100 equal parts, called degrees, the interval between freezing and boiling water.