PHY_10_13_V2_LP_Air humidity,dew point

Long-term plan unit:  Liquid and solid bodies

School:

Date:

Teacher name:

Grade: 10 Physics

Number present:

absent:

Theme of the lesson

Air humidity, dew point

Learning objectives(s) that this lesson is contributing to

10.2.4.1 – to define relative air humidity.

Lesson objectives

-          to know and understand what absolute and relative humidity is;

-          to know and understand what is meant by dew point;

-          to know and understand the principle of device operation for measuring air humidity;

-          to be able to determine the relative humidity.

Evaluation criteria

A student has achieved a learning goal if ...

-           gives the definition of absolute and relative humidity, dew point;

-          describes the principle of device operation for measuring air humidity;

-          determines the relative humidity.

Language Objectives

Subject-Specific Vocabulary and Terminology:

Absolute humidity, relative humidity, air volume, water vapor density temperature

Useful Sets of Phrases for Dialogue and Writing:

There is a special table in which saturated water vapor density is given for each temperature value and pressure.

Cross-curricular links

On Geography lessons students studied that the two-thirds of the Earth surface is covered by water. Water occupies about 71 % of the globe. The evaporation continuously occurs from the surface of various reservoirs at any temperature.

In addition, from Biology lessons they know that different living organisms contain 50 to 99.7 % water, which also evaporates. Therefore, the atmosphere of the earth always contains water vapor.

ICT skills

1) the development of language skills, writing skills and skills of working with charts

Previous learning

Students are familiar with the atmosphere of the Earth, which they have studied in 7 grade, and they knew that it consists of a mixture of different gases, besides that there is water vapor in the air.

Course of the lesson

Planned timings

Planned activities at the lesson

Resources

Beginning

6 min

(T, W) Organizational moment

Task. Actualization of needed knowledge using strategy think – pair – share.

Air humidity. (Humidity - the amount of water vapor in the air; one of the most significant characteristics of weather and climate).

Absolute humidity (Absolute humidity is the mass of water vapor contained in 1 m3 of air, or the density of water vapor in the air).

Relative humidity (Relative humidity of air is the value equal to the ratio of the density of water vapor in the air (absolute humidity) to the density of saturated water vapor at this temperature).

Dew point (The temperature at which the steam in the air becomes saturated during the cooling process is called the dew point).

Hygrometer (Hygrometer-a device used for measuring air humidity. There are several types of hygrometers, the action of which is based on different principles: weight, hair, film, etc.)

Aim: adjust students to study, say the terminology on this topic for a deeper understanding of the studying material.

Teacher’s action: give the task and monitor student’s work.

Student’s action: students think about their definition, discuss in pairs and share with all class.

Feedback: teacher-student, student-student 

Define the topic of the lesson and lesson’s objectives.

Papers with words

Middle

7-10 min

20 min

3 min

Task: humidity worksheet

Aim: to know and understand what absolute and relative humidity is; to know and understand what is meant by dew point;

Task description: answer for the question, compare and fill empty space.

Teacher’s action: organize the students’ work, and check student’s work.

Student’s action: work individually.

Feedback: teacher-student

JIGSAW

Task: group work. Solving problems

Aim: to be able to determine the relative humidity.

Teacher’s action: organize the students’ work.

Student’s action: students work in groups, and then present their results to other groups and evaluate each other.

Feedback: teacher-student

Task: group work. Discuss in groups following question.

WHY PRODUCTS QUICKLY DRY IN A REFRIGERATOR?

In the refrigeration chamber, the coldest place, the evaporator, is at the top, from where the cold and therefore heavy air descends. In contact with warmer products and the walls of the refrigerator, the air is heated, and its relative humidity decreases, because heated air is able to absorb more moisture than cold. Thus, the cold air, when heated, immediately becomes dry and takes away some of the moisture from the products. Then warm, which means that the light air rises up to the evaporator, where it cools to its original temperature, but its humidity is higher than the original because of the water taken from the products. This is repeated several times until the relative air humidity exceeds 100%, and then droplets of water or ice crystals appear on the surface of the evaporator. So the air circulating through the refrigerator “carries on” water from warmer products to a cooler evaporator. At the same time, the products, losing water, are cooled, because they lose the heat needed for evaporation. It is easy to calculate, for example, that a cucumber weighing 50 g, having lost only 0.1 g of moisture, will cool down by more than a degree. Therefore, dry foods are cooled in the refrigerator more slowly than wet ones. In general, it is better to store food in the refrigerator in a sealed container or in a moisture-proof film, although they will certainly cool down more slowly. To speed up air circulation and cooling of products, fans are used in modern models of refrigerators.

Feedback: teacher-student

PHY_10_13_V2_DM_Air humidity,dew point

Worksheet

PHY_10_13_V2_DM_Air humidity,dew point

Worksheet

App 2

End

1 min

 (W) Students’ Reflection

1. What went well?

2. EBI?

3. MRI.

Home task:

Differentiation – how do you plan to give more support? How do you plan to challenge the more able learners?

Assessment – how are you planning to check students’ learning?

Health and safety regulations

Give problem questions

Student-student assessment

Student-teacher assessment

Rules of Technics of Safety at chemistry room

Reflection

Were the lesson objectives/learning objectives realistic? Did all learners achieve the LO?

If not, why?

Did my planned differentiation work well?

Did I stick to timings?

What changes did I make from my plan and why?

Use the space below to reflect on your lesson. Answer the most relevant questions from the box on the left about your lesson. 

Summary evaluation

What two things went really well (consider both teaching and learning)?

1:

2:

What two things would have improved the lesson (consider both teaching and learning)?

1:

2:

What have I learned from this lesson about the class or achievements/difficulties of individuals that will inform my next lesson?