Physics - Senior Secondary 2 - Heat Energy

TERM: 1^ST TERM

WEEK: 1

Class: Senior Secondary School 2
Age: 16 years
Duration: 40 minutes for each of 5 periods
Date:
Subject: Physics
Topic: Heat Energy
Subtopics:

• Temperature and its measurement
• Types of thermometer
• Absolute scale of temperature

SPECIFIC OBJECTIVES:
By the end of the lesson, students should be able to:

1. Define temperature and understand its significance in heat energy.
2. Identify the different types of thermometers.
3. Explain the absolute scale of temperature (Kelvin scale).
4. Understand the relationship between temperature and heat.
5. Measure temperature using various thermometers.

INSTRUCTIONAL TECHNIQUES:

• Explanation
• Demonstration
• Questions and answers
• Hands-on activity: Calibration of a thermometer in the Celsius scale
• Video clips on temperature scales and types of thermometers

INSTRUCTIONAL MATERIALS:

• Thermometers (Celsius, Kelvin, and Fahrenheit)
• Laboratory setup (boiling water, ice, thermometer, beakers)
• Physics textbook
• Whiteboard markers
• Videos on temperature and its measurement

INSTRUCTIONAL PROCEDURES

PERIOD 1-5

PRESENTATION

STEP 1: INTRODUCTION

• The teacher will ask students about their understanding of heat and temperature.
• Students will share their prior knowledge, and the teacher will introduce the concept of temperature as a measure of heat.

STEP 2: EXPLANATION

• The teacher explains the meaning of temperature: the degree of hotness or coldness of a substance.
• Introduction to temperature scales (Celsius, Fahrenheit, and Kelvin).
• The teacher explains that temperature is the average kinetic energy of particles in a substance.

STEP 3: DEMONSTRATION

• The teacher demonstrates how to measure the temperature of boiling water using a thermometer.
• Students are encouraged to participate in measuring temperature with different thermometers.
• Discussion on how each thermometer works and the unit of temperature (°C, °F, K).

STEP 4: CALIBRATION OF THERMOMETER

• The teacher will guide students on how to calibrate a thermometer in the Celsius scale.
  Procedure:

1. Place the thermometer in ice water (0°C) and mark this point.
2. Place the thermometer in boiling water (100°C) and mark this point.
3. Use these two fixed points to calibrate the thermometer.

Solved Example: For the calibration process, suppose the thermometer reads 98°C in boiling water. The actual temperature should be 100°C. Adjust the thermometer to reflect the correct temperature. Similarly, for ice water, if the thermometer reads -2°C, the actual temperature should be 0°C. Correct the readings accordingly.

• Students will carry out the calibration in groups.

STEP 5: NOTE TAKING

• The teacher writes a summary note on the board, which students will copy.

NOTE

Heat Energy:

• Temperature is a measure of the average kinetic energy of particles in a substance.
• Types of Thermometers:

1. Mercury Thermometer: Contains mercury that expands and contracts with temperature changes.
2. Alcohol Thermometer: Uses colored alcohol that expands with heat.
3. Digital Thermometer: Measures temperature electronically.
4. Bimetallic Thermometer: Uses a metal strip that bends with temperature changes.

• Absolute Scale of Temperature (Kelvin Scale):

• The Kelvin scale starts at absolute zero, where all molecular motion stops.
• The freezing point of water is 273.15 K and the boiling point is 373.15 K.
• Formula to convert Celsius to Kelvin:
  K=°C+273K = °C + 273

EVALUATION

1. What is temperature?
2. List and describe three types of thermometers.
3. What is the Kelvin scale, and how is it related to the Celsius scale?
4. How do you calibrate a thermometer in the Celsius scale?

CLASSWORK:

• Write the conversion formulas for Celsius to Fahrenheit and Celsius to Kelvin.
• List the steps for calibrating a thermometer.

CONCLUSION:

• The teacher will review the students' answers and provide positive feedback.

The students are encouraged to reflect on the importance of accurate temperature measurement in daily life.