Lesson 4 States of Matter and Brownian Motion

8/3/2019 Lesson 4 States of Matter and Brownian Motion

1/19

Do now!

.Can you readthrough thework we did

last lesson onpressure and

depth?


2/19

Last lesson

Understand that the pressure at a point ina gas or liquid which is at rest acts equallyin all directions

Recall and use the relationship forpressure difference:

pressure difference = height density g

p = hg


3/19

All directions

.


4/19

Pressure and depth

.

Pressure increases with depth(P = gh)

The pressure acts in alldirections


5/19

.

Pressure difference between top andbottom = gh

= 1000 kg/m3x9.8x0.2

= 1960 N/m2

0.2m


6/19

This lesson

Understand that a substance can change statefrom solid to liquid by the process of melting

Understand that a substance can change state

from liquid to gas by the process of evaporationor boiling

Recall that particles in a liquid have a randommotion within a close-packed structure

Recall that particles in a solid vibrate about fixedpositions within a close-packed regular structure

Understand the significance of Brownian motion


7/19

Stand up!

.


8/19

Draw the sentence

1. 2. 3. 4.

5. 6. 7. 8.


9/19


10/19

Solids, liquids and gases

.


11/19

Properties of solids, liquids andgases

.

Make notesof the

following

slides if you

wish!


12/19

Solids

Fixed shape

Cannot flow

Difficult to compress Generally dense


13/19

Liquids

Shape can change

Can flow

Not easy to compress Generally dense


14/19

Gases

Shape can change

Can flow

Easy to compress Low density


15/19

Changes of state

.


16/19

Brownian motion

.


17/19

Brownian motion Fat droplets in milk

.

Einstein's Explanation of BrownianMotion http://www.practicalphysics.org/fileLibrary/wmv/brownian_

Brownian

Motion
http://galileoandeinstein.physics.virginia.edu/more_stuff/Applets/brownian/brownian.htmlhttp://galileoandeinstein.physics.virginia.edu/more_stuff/Applets/brownian/brownian.htmlhttp://www.practicalphysics.org/fileLibrary/wmv/brownian_motion.wmvhttp://www.practicalphysics.org/fileLibrary/wmv/brownian_motion.wmvhttp://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=24http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=24http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=24http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=24http://www.practicalphysics.org/fileLibrary/wmv/brownian_motion.wmvhttp://www.practicalphysics.org/fileLibrary/wmv/brownian_motion.wmvhttp://www.practicalphysics.org/fileLibrary/wmv/brownian_motion.wmvhttp://galileoandeinstein.physics.virginia.edu/more_stuff/Applets/brownian/brownian.htmlhttp://galileoandeinstein.physics.virginia.edu/more_stuff/Applets/brownian/brownian.html


18/19

.

Brownian motion is the seeminglyrandom movement of particles suspendedin a fluid (i.e. a liquid or gas). It is due to

the instantaneous imbalance in thecombined forces exerted by collisions ofthe particle with the much smaller liquid

molecules surrounding it.


19/19

What shall we do now?

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Documents

Lesson 4 States of Matter and Brownian Motion