1. Book 1 Section 1.1 Temperature
Is heat wave coming?
Temperature—a measure of hotness
The Celsius temperature scale
Check-point 1
Temperature and particle motion
Check-point 2 1 2 3
Book 1 Section 1.1 Temperature

2. Book 1 Section 1.1 Temperature
Is heat wave coming?
…it is believed that the temperature in New York will go up to 70 degrees this week… ? ? ?
Which temperature scale is it referring to?
Book 1 Section 1.1 Temperature

3. 1 Temperature–a measure of hotness
Hot pot
Ice-cream
We can feel different degrees of ‘hotness’ from different objects.
How to compare their hotness accurately?
Book 1 Section 1.1 Temperature

4. 1 Temperature–a measure of hotness
To compare the hotness of objects, we need to measure their temperatures.
Temperature is a measure of the degree of hotness of an object.
Temperature can be measured in degrees Celsius (C).
Book 1 Section 1.1 Temperature

5. 1 Temperature–a measure of hotness
Some different temperatures in Celsius temperature scale:
Bunsen flame 1000 C
surface of sun 5500 C
melting ice 0 C
human body 37 C
Warm room 25 C
boiling water 100 C
bulb filament 2500 C
Absolute zero –273 C
Book 1 Section 1.1 Temperature

6. 2 The Celsius temperature scale
a Defining the Celsius temperature scale
Celsius Scale: most commonly used scale
Defined by choosing two fixed points:
1. Ice point: temp of pure melting ice at normal atm pressure
2. Steam point: temp of steam over pure boiling water at normal atm pressure
Book 1 Section 1.1 Temperature

7. a Defining the Celsius temperature scale
Ice point  lower fixed point
Steam point  upper fixed point
(100C)
Lower fixed point
Upper fixed point
divisions . . .
. . .
1 division  1 degree (1C)
Book 1 Section 1.1 Temperature

8. b Calibrating a thermometer on the Celsius temperature scale
1/100 of the interval = 1 C
0 °C
100 °C
2. Mark the liquid level
4. Mark the liquid level
3. Put in boiling water
1. Put in melting ice
Book 1 Section 1.1 Temperature

9. b Calibrating a thermometer on the Celsius temperature scale
Let’s begin
1.1 Calibration of thermometer (liquid-in-glass)
Simulation
Calibrating a liquid-in-glass thermometer
Example 1
Book 1 Section 1.1 Temperature

10. Book 1 Section 1.1 Temperature
Check-point 1 – Q1
Which of the following about the Celsius scale is incorrect?
A Lower fixed point = 0 C Upper fixed point = 100 C
B (upper fixed point – lower fixed point)/100  1 division = 1 degree Celsius
C It is the only temp scale available.
D T > 100 C and T < 0 C are possible.
Book 1 Section 1.1 Temperature

11. Book 1 Section 1.1 Temperature
Check-point 1 – Q2
The calibration graph of a thermometer:
15 cm
60 C
When T = 60 C, L = _______.
Book 1 Section 1.1 Temperature

12. 3 Temperature and particle motion
Kinetic Theory:
All matters are made up of tiny particles which are constantly in motion.
Particles attract/repel each other
close particles
distant particles
weak attraction
strong attraction
Book 1 Section 1.1 Temperature

13. 3 Temperature and particle motion
Particles of...
solid
liquid
gas
fixed volume and shape
fixed volume but irregular shape
irregular volume and shape
very close  strong attraction
less close  strong attraction
far apart  weak attraction
Book 1 Section 1.1 Temperature

14. 3 Temperature and particle motion
solid
liquid
gas
fixed positions; can vibrate only
no fixed positions; can change position
no fixed positions; move at very high speeds in random motion
Simulation
1.2 Models of solid, liquid and gas
Book 1 Section 1.1 Temperature

15. 3 Temperature and particle motion
Temperature of an object is a measure of the average K.E. of its particles.
T   particles vibrate more rapidly or move faster
T   particles slow down
same average K.E.  same temp
average K.E. is minimum  absolute zero
Book 1 Section 1.1 Temperature

16. Book 1 Section 1.1 Temperature
Check-point 2 – Q1
Tommy says:
‘This object is extremely cold!’
Which of the following cannot be the temp of the object?
A –300 C
No temperature can be lower than absolute zero (–273 C)!
B –30 C
C 0 C
D 3 C
Book 1 Section 1.1 Temperature

17. Book 1 Section 1.1 Temperature
Check-point 2 – Q1
Which of the following is incorrect?
A Gas particles are far apart and move at very high speeds.
B Temp rises  particles move faster
C Temp is a measure of total KE
D Same temp  particles have same average KE
Book 1 Section 1.1 Temperature

18. Book 1 Section 1.1 Temperature
The End
Book 1 Section 1.1 Temperature