1
10/1
PHYSICS 10
TRUNG VUONG HIGH SCHOOL
Warmly welcome teachers and students
Q.1: Among the following quanlities, which isn’t the state parameter of an amount of gas?
A
B
C
D
Volume

Mass
Absolute temperature
Pressure
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Q.2: Among the following relations, which isn’t suitable to Boyle-Mariotte’s law?
A
C
B
D
p ~ 1/V
V ~ p
V ~ 1/p
p1V1 = p2V2
Q.3: Which is suitable to the Boyle-Mariotte’s law?
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C
p ~ V
Q.4: In the coordinate system (p,V), which of the following expressing lines is an isotherm?
A
B
C
D
Hyperbolic line
The line extends through the coordinate origin
The line doesn’t go through the coordinate origin
Parabolic line
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Lesson 30 : ISOCHORIC PROCESS
CHARLES’ LAW
I. Isochoric process
II. Charles’ law
III. Isochoric line
CONTENT
CHARLES
(1746-1823)
French physicist
IV. Application
Gr. 1
Gr. 2
Gr. 3
Gr. 4
What notes does the experiment in Figure 30.1 allow us to draw about the relation between the pressure and temperature when the volumes is unchanged?
I. Isochoric process
The process of state transformation when the volumes is unchanged is the isochoric process.
Lesson 30 : ISOCHORIC PROCESS
CHARLES’ LAW
Lesson 30 : ISOCHORIC PROCESS
CHARLES’ LAW
II. Charles’ law
1. Experiment
The experiment allows us to follow the changed of pressure of an amount of gas versus the temperature in the isochoric process.
* The results of the experiment:
2,54
2,59
2,58
2,61
C1: Calculate values of P/T in table. From that, draw the relation between p and T in the isochoric process
Conclusion :
Seen : P~T or P/T = const
Lesson 30 : ISOCHORIC PROCESS
CHARLES’ LAW
373,0
324,5
297,0
273,0
2. Charles’ law.
In the isochoric process of a certain amount of gas, the pressure is directly proportional to the absolute temperature.
 
 
 
Lesson 30 : ISOCHORIC PROCESS
CHARLES’ LAW
Example : Calculate pressure and absolute temperature of an amount of gas at 30oC, known that the pressure at 0oC is 1.20.105 Pa and the volume of gas is unchanged .
Lesson 30 : ISOCHORIC PROCESS
CHARLES’ LAW
Because the volume of gas is unchanged:
 
 
 
 p2= 1,33.105 Pa
Lesson 30 : ISOCHORIC PROCESS
CHARLES’ LAW
III. Isochoric line
770
838
T(K)
715
273
324,5
948
p (mmHg)
297
373
Use the data in the table of experiment result to draw the line expressing the change of the pressure versus the absolute temperature in the coordinate system (p,T).
The line expressing the change of the pressure versus temperature when the volume is unchanged is called isochor.
O
V
What characteristics does this expressing line have?
Lesson 30 : ISOCHORIC PROCESS
CHARLES’ LAW
III. Isochoric line
In the coordinate system (p,T), the isochor is the line that if it is extended, it will go through the coordinate origin.
O
V
The line above is corresponding to the smaller volume.
For different volumes of the same amount of gas, we have different Isochoric line
P
T(K)
O
 
 
Lesson 30 : ISOCHORIC PROCESS
CHARLES’ LAW
Because: p1 > p2 so V1< V2
p1
p2
p
Lesson 30 : ISOCHORIC PROCESS
CHARLES’ LAW
Isochoric line
will go through the coordinate origin.
Isochoric line
will perpendicular to the OV axis
Isochoric line
will perpendicular to the OV axis
V
T(K)
p
V
O
O
O
Lesson 30 : ISOCHORIC PROCESS
CHARLES’ LAW
IV. Application
When making an incandescent bulb, people fill inert gas with low pressure because when the lamp is on, the temperature of the incandescence increases, which makes the gas pressure in the bulb increases as equivalently as the air pressure outside so that the bulb is not broken..
Why are incandescent bulbs filled with inert gas?
Lesson 30 : ISOCHORIC PROCESS
CHARLES’ LAW
IV. Application
The tire is inflated in the sun ⇒ the gas temperature in the tire increases ⇒ the gas molecules fluctuate sharply ⇒ the pressure increases ⇒ the tire is exploded.
Why do inflated tires in the sun often explode?
Why does the pressure cooker have a safety valve?
Lesson 30 : ISOCHORIC PROCESS
CHARLES’ LAW
IV. Application
Why should the glass bottle be closed tightly?
Q.1: In the following relations, which is not suitable to the Charles’ law?
PRACTICE
Q.2: Which of the following relations is suitable to the Charles’ law?
B
p ~ t
B
 
Q. 3: In the coordinate system (p,T), which of the following expressing lines is an isochor?
A
C
B
D
Hyperbolic line
The line extends through the coordinate origin
The line doesn’t go through the coordinate origin
The line cut th axis p at the point p = po
Q. 4: A pot contains an of gas at 300C and the pressure 2 bar ( 1 bar = 105 Pa). How should the temperature rise to double the pressure?
 
State 2
T2 = ?
P2 = 2.P1
Because the volume of gas is unchanged:
 
 
 
 
Q.5: A car tire contains air with the pressure of 5 bar and the temperature of 25oC. When the car runs fast, the tire gets hot, making the temperature of air in the tire increase up to 50oC. Calculate the pressure of air in the tire at this time ?
 
 
Because the volume of gas is unchanged:
 
 
 
ISOCHORIC PROCESS
CHARLES’ LAW
I. Isochoric process
III. Isochoric line
II. Charles’ law
V = const.
In the coordinate system (p,T), the isochor will go through the coordinate origin.
 
 
In the coordinate system (p,V), (T,V) Isochoric line will perpendicular to the OV axis
UNIT 3. MUSIC
GETTING STARTED
THANKS FOR YOUR ATTENTION !