Charles’s Law - 9.4 | 9. Behaviour of Perfect Gas and Kinetic Theory | ICSE Class 11 Physics
K12 Students

Academics

AI-Powered learning for Grades 8–12, aligned with major Indian and international curricula.

Academics
Professionals

Professional Courses

Industry-relevant training in Business, Technology, and Design to help professionals and graduates upskill for real-world careers.

Professional Courses
Games

Interactive Games

Fun, engaging games to boost memory, math fluency, typing speed, and English skills—perfect for learners of all ages.

games

Interactive Audio Lesson

Listen to a student-teacher conversation explaining the topic in a relatable way.

Understanding Charles's Law

Unlock Audio Lesson

Signup and Enroll to the course for listening the Audio Lesson

0:00
Teacher
Teacher

Today, we’re discussing Charles's Law. Who can tell me what this law states?

Student 1
Student 1

It says that the volume of a gas increases with temperature, right?

Teacher
Teacher

Exactly! At constant pressure, the volume of a gas is directly proportional to its absolute temperature in Kelvin. This means as the temperature goes up, the volume also goes up. Can anyone share the formula for this law?

Student 2
Student 2

Is it V/T = constant?

Teacher
Teacher

Yes! Great job! This formula helps us understand the relationship quantitatively. What does a graph of this law look like?

Student 3
Student 3

It’s a straight line, right? Like a linear graph?

Teacher
Teacher

Correct! A Volume vs. Temperature graph shows that direct proportionality as a straight line. Now, why do you think this is important?

Student 4
Student 4

It helps explain how hot air balloons work, right?

Teacher
Teacher

Exactly! When the air inside the balloon heats up, it expands, increasing the volume and allowing the balloon to rise. Let’s summarize: Charles’s Law shows that the volume of a gas increases with temperature at constant pressure – remember the formula V/T = constant!

Applications of Charles's Law

Unlock Audio Lesson

Signup and Enroll to the course for listening the Audio Lesson

0:00
Teacher
Teacher

Let’s dive deeper! What are some real-life applications of Charles's Law?

Student 1
Student 1

The hot air balloon example is a big one!

Teacher
Teacher

Absolutely! And can anyone think of another example?

Student 2
Student 2

What about car tires? Their air expands when they heat up.

Teacher
Teacher

That’s right! As tires heat up from driving, the air inside expands, which can increase the pressure -- but we are focusing on volume. Does anyone have a memory aid to remember this law?

Student 3
Student 3

I remember the phrase 'Volume and Warmth Go Hand in Hand' helps me recall that volume increases with temperature!

Teacher
Teacher

Perfect mnemonic! So, repeating key concepts here: Volume increases with temperature at constant pressure, following the formula V/T = constant.

Graphical Representation and Understanding

Unlock Audio Lesson

Signup and Enroll to the course for listening the Audio Lesson

0:00
Teacher
Teacher

Let’s analyze the graph of Charles’s Law. What shape do you see?

Student 4
Student 4

It looks like a straight line, starting from the origin.

Teacher
Teacher

That's correct! A straight line indicates a linear relationship. How does this relate to the formula we discussed?

Student 1
Student 1

It shows that if you plot volume on one axis and temperature on the other, they increase together.

Teacher
Teacher

Exactly! This visualization reinforces the concept. Can someone explain why the absolute temperature is important?

Student 2
Student 2

Because if we used Celsius, it wouldn’t show the same proportionality near zero!

Teacher
Teacher

Right! Always remember, volume must change with absolute temperature in Kelvin to maintain that relationship. Summarizing again: Charles’s Law shows us the direct relationship through a linear graph!

Introduction & Overview

Read a summary of the section's main ideas. Choose from Basic, Medium, or Detailed.

Quick Overview

Charles's Law states that the volume of a gas is directly proportional to its absolute temperature at constant pressure.

Standard

In Charles's Law, as the temperature of a gas increases, so does its volume, provided the pressure remains constant. This relationship can be represented mathematically and graphically, illustrating its significance in various applications, such as in hot air balloons.

Detailed

Charles’s Law

Charles’s Law is a fundamental principle in the study of gases, which states that at constant pressure, the volume of a gas is directly proportional to its absolute temperature measured in Kelvin. Mathematically, this relationship is expressed as:

Formula: V/T = constant

This means that if the temperature of a gas increases, the volume will also increase, as long as the pressure does not change. The graphical representation of Charles’s Law is a straight line on a Volume vs. Temperature graph, demonstrating a linear relationship. A practical example of this law can be observed with hot air balloons. When the air inside the balloon is heated, it expands, causing the volume to increase and resulting in the balloon rising. Understanding Charles’s Law is crucial for interpreting the behavior of gases under varying temperature conditions, tying back to the principles of the Kinetic Theory of Gases.

Youtube Videos

Class 11th Physics Kinetic theory of Gases in One Shot with Ashu Sir
Class 11th Physics Kinetic theory of Gases in One Shot with Ashu Sir
KINETIC THEORY OF GASES In One Shot || NEET Physics Crash Course
KINETIC THEORY OF GASES In One Shot || NEET Physics Crash Course
Kinetic Theory of Gases FULL CHAPTER | Class 11th Physics | Arjuna JEE
Kinetic Theory of Gases FULL CHAPTER | Class 11th Physics | Arjuna JEE
KINETIC THEORY OF GASES in 1Shot: FULL CHAPTER COVERAGE (Concepts+PYQs) | Prachand NEET 2024
KINETIC THEORY OF GASES in 1Shot: FULL CHAPTER COVERAGE (Concepts+PYQs) | Prachand NEET 2024
KINETIC THEORY OF GASES (KTG) in 30 minutes || Complete Chapter for NEET
KINETIC THEORY OF GASES (KTG) in 30 minutes || Complete Chapter for NEET
CLASS 11, PHYSICS ,Ch.- 9,  BEHAVIOUR OF PERFECT GASES AND KINETIC THEORY OF GASES
CLASS 11, PHYSICS ,Ch.- 9, BEHAVIOUR OF PERFECT GASES AND KINETIC THEORY OF GASES
Behaviour Of Perfect Gas And Kinetic Theory
Behaviour Of Perfect Gas And Kinetic Theory
Lecture 1: Kinetic Theory of Gases, Unit: Behaviour of Perfect Gas & Kinetic Theory, Class 11th
Lecture 1: Kinetic Theory of Gases, Unit: Behaviour of Perfect Gas & Kinetic Theory, Class 11th
11 chapter 13 Physics || Kinetic Theory 01: Introduction to KTG and Equation of States (Gas Laws )
11 chapter 13 Physics || Kinetic Theory 01: Introduction to KTG and Equation of States (Gas Laws )

Audio Book

Dive deep into the subject with an immersive audiobook experience.

Statement of Charles’s Law

Unlock Audio Book

Signup and Enroll to the course for listening the Audio Book

At constant pressure, the volume of a gas is directly proportional to its absolute temperature (in Kelvin).

Detailed Explanation

Charles’s Law tells us how the volume of a gas changes when the temperature changes, as long as the pressure stays the same. This means that if we heat the gas, its volume will increase, and if we cool it, the volume will decrease. The relationship is direct, meaning that higher temperatures lead to larger volumes.

Examples & Analogies

Think of a balloon: when you heat the air inside the balloon, the gas expands, making the balloon larger. However, if you put the balloon in a cold environment, the volume decreases as the air inside cools down.

Formula of Charles’s Law

Unlock Audio Book

Signup and Enroll to the course for listening the Audio Book

V/T = constant.

Detailed Explanation

The formula V/T = constant shows that the ratio of volume (V) to temperature (T) is always the same for a specific amount of gas under constant pressure. This means that if you know the volume and temperature of a gas in one situation, you can predict what will happen in another situation as long as the pressure doesn't change.

Examples & Analogies

Imagine you’re a chef and you need to calculate how much dough to make. If you know how much dough you can put in the oven at a certain temperature, you can figure out how much to make if you change the oven temperature, keeping all other factors the same.

Graph of Charles’s Law

Unlock Audio Book

Signup and Enroll to the course for listening the Audio Book

Volume vs Temperature → Straight line.

Detailed Explanation

When we plot the relationship of volume on the y-axis and temperature on the x-axis, the result is a straight line that passes through the origin. This linear relationship reinforces the idea that as temperature increases, volume increases in a predictable manner.

Examples & Analogies

If you were to graph how your bicycle tire expands in the heat, you would see a straight line. More heat means greater volume of air, aligning perfectly with the concept of Charles’s Law.

Real-Life Example of Charles’s Law

Unlock Audio Book

Signup and Enroll to the course for listening the Audio Book

Hot air balloon rises because heated air expands, increasing volume.

Detailed Explanation

A hot air balloon is a practical example of Charles’s Law in action. When the air inside the balloon is heated, it expands and takes up more space. Since the volume of the heated air is greater compared to the cooler air outside the balloon, the balloon becomes buoyant and rises.

Examples & Analogies

Imagine you have a sealed bag filled with air. If you heat that bag on a stove, the air inside expands, causing the bag to puff up. Just like that bag, a hot air balloon rises as the heated air inside increases in volume compared to the cooler, denser air outside.

Definitions & Key Concepts

Learn essential terms and foundational ideas that form the basis of the topic.

Key Concepts

  • Direct Proportionality: As temperature increases, volume also increases at constant pressure.

  • Absolute Temperature: Temperature must be measured in Kelvin for accurate proportionality.

  • Graph: The relationship between volume and temperature is represented as a straight line on a graph.

Examples & Real-Life Applications

See how the concepts apply in real-world scenarios to understand their practical implications.

Examples

  • A hot air balloon rises as the air inside it is heated, expanding and increasing its volume.

  • In an old-fashioned thermometer, the increase in liquid volume corresponds to rising temperature.

Memory Aids

Use mnemonics, acronyms, or visual cues to help remember key information more easily.

🎵 Rhymes Time

  • When the warmth is high, the volume will fly, up to the sky, oh my!

📖 Fascinating Stories

  • Imagine a hot air balloon. When the sun heats the air inside, it expands and fills the balloon, causing it to rise high in the sky.

🧠 Other Memory Gems

  • V for Volume and T for Temperature, both go up together!

🎯 Super Acronyms

CVT

  • Charles's Volume Temperature relation.

Flash Cards

Review key concepts with flashcards.

Glossary of Terms

Review the Definitions for terms.

  • Term: Charles's Law

    Definition:

    The law stating that the volume of a gas is directly proportional to its absolute temperature at constant pressure.

  • Term: Absolute Temperature

    Definition:

    The temperature measured on a scale where 0 is absolute zero, usually measured in Kelvin.

  • Term: Proportional

    Definition:

    A relationship where one quantity varies directly with another.

  • Term: Volume

    Definition:

    The amount of space occupied by a substance, commonly measured in liters or cubic meters.