Download - Physics M3 Brownian Motion

BROWNIAN MOTION

Physics Module 3 Unit 2 Lesson 1o

Image Source - http://en.m.wikipedia.org/wiki/Brownian_motion

OBJECTIVES

WHAT IS BROWNIAN MOTION?

DISCOVERY OF BROWNIAN

MOTION

OBSERVING BROWNIAN

MOTOIN

DEDUCTIONS FROM BROWNIAN

MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ

XXIntroduction

• What does the kinetic theory state about matter?

• What effect does an increase in thermal energy have on kinetic energy of particles.

• Go to introductory activity on the next slide.

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ

XXIntroductory Activity 10.1

1. Form into groups no more than four(4) students.

2. Materials: microscope (100-400x), dirt, water

3. Procedure:• Mix dirt in some water.• Allow to settle for approximately 8

min.• Observe water surface with a

microscope (100-400x).• Click the next button for questions on

activity.

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ

XXActivity 10.1 – Question 1

Question 1: What did you observe?Type your answers in the box and then click CHECK to see possible answers.

Tiny particles moving all over the place when they are

hitting larger particles.

CHECKNEXT NEXT

QUESTIONQUESTION

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ


How would you describe the motion of the smaller particles?

Random or haphazard. That is the motion of

the particles is unpredictable. CHECK

NEXT NEXT QUESTIONQUESTION

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ


Which particle is larger, water or dirt?

Water particlesCHECK


OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ


Which particle is moving with the greater energy?

Dirt particles

CHECK


OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ


What conclusion can you make?

Smaller dirt particles with greater energy are

hitting against larger water particles.CHECK


OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ


What change would be observed if thermal energy was added?

The tiny dirt particles would be colliding with larger water particles with greater frequency.

CHECK

END OF END OF ACTIVITYACTIVITY

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ

XXObjectives

As a result of this lesson, the student will be able to:

1.describe Brownian motion.

2.observe Brownian motion under a microscope, and explain what causes it.

3.perform activities which relate to Brownian movement.

4.use the kinetic theory to explain Brownian motion.

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ

XXWhat is Brownian Motion?

Brownian motion describes :

The random movement of tiny microscopic particles suspended in a liquid or gas, caused by collisions between these particles and the molecules of a liquid or gas.

The random movement of tiny microscopic particles suspended in a liquid or gas, caused by collisions between these particles and the molecules of a liquid or gas.

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ

XXDescription of Brownian motion

• When observing pollen grains under a microscope, Robert Brown a Scottish biologist noticed that the pollen grains which were suspended in water were moving in a random haphazard way.

• Brown theorized that the molecules of water were colliding with the pollen grains. Random movement of the pollen grains was known as Brownian motion.

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ

XXDescription of Brownian motion (cont.)

• The same effect was noticed when smoke was passed in a glass cell with air.

• Bright specks were observed to be moving jerky under a microscope. This implied that the smoke particles were bombarded against air particles which changed its direction continuously.

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ

XX Demonstrating Brownian motion

Robert Brown, a Scottish biologist placed pollen grains in water and viewed it under a microscope.

Click HERE to see view under microscope.

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ

XX

http://weelookang.blogspot.com/2010/06/ejs-open-source-brownian-motion-gas.html

Demonstrating Brownian motion

View under microscope

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ

XXDeductions

1. Smoke is made up of particles2. Since specks (smoke particles) are

moving it implies that they are continuously hitting against some other particle (water).

3. Jerky movement is as a result of smoke particles hitting against invisible air particles.

4. Temperature increase results in an increased rate of bombardment. (link kinetic theory to this)

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ

XXActivity 10.2

View activity at -http://www.kscience.co.uk/animations/brownian.swf and then answer the following questions.

1.Describe the motion of the different particles in the video.

2.Add heat to the particles and state your observations.

3.Remove heat from the particles and state your observations.

4.What effect does temperature have on Brownian motion of particles?

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ


Describe the motion of the different particles in the video.

The single light coloured particle is seen moving in a haphazard way.

CHECK

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ


Add heat to the particles and state your observations.

All the particles started to move faster. The single light coloured particle started to hit darker particles more frequently and increases its haphazard movement.

CHECK

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ


Remove heat from the particles and state your observations.

All the particles started to move slower. The single light coloured particle started to hit darker particles less frequently and decreases its haphazard movement. CHECK

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ


What effect does temperature have on Brownian motion of particles?

The greater the temperature the greater the effect of Brownian motion

CHECK

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ

XXThe following is a metaphor for Brownian Motion.

Consider a bread crumb which is 1/2 centimeter wide. Imagine this bread crumb on a sea of soldier ants in an ant nest. Because the ants are so excited, they are all trying to crab the bread crumbs.

•Describe how the different parts of the story relate to the experiment by Robert Brown.•Go to the short QUIZ on the next slide.

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ

XXQUIZ

• Are you ready to test yourself? • There are three multiple choice items and one free response that you are required to do in relation to the Brownian motion metaphor.

• For each multiple choice item, click on the letter of the correct response and then click the button ‘NEXT QUESTION’ to continue. For the free response item, click CHECK your answer.

• Click the START QUIZ button to begin.

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START QUIZ!

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ

XXQUIZ: Question 1

What does the bread crumb represent?

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A. Water molecules

B. Pollen grains

C. A pollen grain

FEEDBACK

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ

XXQuiz: Feedback to Question 1

What does the bread crumb represent?

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NEXT QUESTION

The bread crumb moving reflects a pollen grain hitting against water molecules.

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ

XXQUIZ: Question 2

What does the colony of ants represent?

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A. a water molecule

C. a pollen grain

B. water molecules

FEEDBACK

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ


What does the colony of ants represent?

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The ants represents the invisible water molecules on which the pollen grains would be bombarding against.

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ

XXQUIZ: Question 3

What does the Ant nest represent?

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A. A container

B. Water molecules

C. The water container

FEEDBACK

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ


What does the Ant nest represent?

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The ant nest would represent the container which holds the water and pollen grain when they are being viewed through the microscope.

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ

XXQuiz: Question 4

Describe the motion of the bread crumb as the ants crab in excitement.

Each ant should be fighting to carry the bread crumb. The bread crumb therefore would not be moving in a fixed order in the nest. The crumb would be moving in a random/haphazard way.

CHECK

Type your answer in the box and then click CHECK to see possible answer.

OBJECTIVES



MOTION

OBSERVING BROWNIAN

MOTOIN


MOTION

BROWNIAN MOTION

METAPHOR

INTRODUCTION

QUIZ

XXEnd of Quiz

• You have reached the end of the quiz. • If you wish to review this lesson, go to the first slide.

• If you have finished viewing the lesson, click the Close (X) button.

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