บูเข้ม 1 atmospherics pressure
TRANSCRIPT
PhysicsAtmospheric Pressurefor Matthayomsuksa 1
Vocabulary
atmospheric pressure(n.)
Vocabulary
experiment (n.)
Vocabulary
measurement (n.)
Vocabulary
barometer(n.)
Vocabulary
circumstance(n.)
Vocabulary
mass(n.)
Vocabulary
elevation (n.)
Vocabulary
overlying (v.)
Vocabulary
mercury (n.)
StructurePassive Voice
In passive sentences, the subject of the verb is not the person or thing (the “agent”) doing the action.
Structure
Subject + auxiliary verb (be) + main verb (past participle) + (by) +…
Note: the main verb is always in its past participle
form.
Structure
Use of the Passive VoiceWe use the passive when:
We want to make the active object more important.
We do not know the active subject.
Structure
Look at these examples:
1. Atmospheric pressure is closely approximated by the hydrostatic pressure.
subjectauxiliary
verb (be)
main verb (past
participle)
Look at these examples:
2. Standard Atmospheric Pressure is used as a reference for gas densities and volumes.
Structure
subjectauxiliary
verb (be)
main verb (past
participle)
StructureLook at these examples:
3. The Standard Atmospheric Pressure is defined at sea-level.
main verb (past
participle)
auxiliary verb (be)
subject
Look at these examples:
4. Any instrument that measures air pressure is called a barometer.
Structure
auxiliary verb (be)
main verb (past
participle)
subject
Text 3Atmospheric pressureAtmospheric pressure is the force per unit
area exerted into a surface by the weight of air above that surface in the atmosphere of Earth. In most circumstances atmospheric pressure is closely approximated by the hydrostatic pressure caused by the weight of air above the measurement point. Low-pressure areas have less atmospheric mass above their location, whereas high-pressure areas have more atmospheric mass above their location. Likewise, as elevation increases, there is less overlying atmospheric mass, so that pressure decreases with increasing elevation.
Standard Atmospheric Pressure
Standard Atmospheric Pressure (atm) is used as a reference for gas densities and volumes. The Standard Atmospheric Pressure is defined at sea-level at 273oK (0oC) and is 1.01325 bar or 101325 Pa (absolute). The temperature of 293oK (20oC) is also used.
Measuring Atmospheric PressureAny instrument that measures air pressure is called
a barometer. The first measurement of atmospheric pressure began with a simple experiment performed by Evangelista Torricelli in 1643. In his experiment, Torricelli immersed a tube, sealed at one end, into a container of mercury. Atmospheric pressure then forced the mercury up into the tube to a level that was considerably higher than the mercury in the container. Torricelli noticed that height of the mercury varied with changes in outside weather conditions. The most common type of barometer used in homes is the aneroid barometer
Figure 1: Diagram showing the construction of Torricelli's barometer.
Figure 2: Aneroid barometer.
Activity
Speaking
Writing
SpeakingExperiment Role-playSituation: You are in the science experiment
contest. You have to present your project, remember to give the following science process
1. Observation2. Hypothesis Forming3. Data Gathering4. Performing Experiement to test you hypothesis5. Results Recording
The rest of other groups are the committee and try to find out the faults by using some questions.
Make a group of 5 I will give you 10 minutes
Writing
Create your own experiment about “Atmospheric Pressure” by using the following materials:
Paper Glass Water
Then write on the paper and present in front of class.
Atmospheric Pressure.