live_tv
Livestream Starting Soon
00
Hours
:
00
Minutes
:
00
Seconds
Up next in 10
Atmospheric pressure is the force exerted by the weight of the air above a surface per unit area
Show More Show Less View Video Transcript
0:00
What is atmospheric pressure?
0:02
Definition: Atmospheric pressure is the
0:04
force exerted by the weight of the air
0:06
above a surface per unit area.
0:09
Explanation: The air around the Earth
0:11
has mass and due to gravity, it presses
0:14
down on everything on the Earth's
0:15
surface. This downward force of air
0:19
creates atmospheric pressure. It is
0:21
greatest at sea level where the air
0:23
column above is largest and decreases
0:26
with increase in altitude because there
0:29
is less air above. Atmospheric pressure
0:32
affects weather, breathing and many
0:34
everyday phenomena. Imagine imagine
0:37
drinking a beverage with a straw. When
0:39
you suck the air out of the straw,
0:41
atmospheric pressure pushes the liquid
0:43
up into your mouth. This simple action
0:47
shows how atmospheric pressure works. In
0:50
simple terms, atmospheric pressure is
0:52
the pressure caused by the air around
0:54
us. Formula or concept. Atmospheric
0:58
pressure is measured using instruments
1:00
like barometers. At sea level, its
1:03
standard value is about 101,325
1:07
pascals. Atmospheric pressure depends on
1:10
height above sea level, density of air,
1:13
weather conditions. Key points caused by
1:16
the weight of air acts in all
1:18
directions. Decreases with altitude.
1:21
Affects weather and climate. Measured in
1:24
Pascals. Examples. Breathing air. Liquid
1:27
rising in a straw. Barometer readings.
1:30
Boiling water at high altitudes.
1:32
Applications. Weather forecasting.
1:35
Aviation and altitude measurement.
1:38
Medical devices. Fluid and gas studies.
1:41
Physics education. Question. Why is
1:44
atmospheric pressure lower on mountains?
1:47
Answer: Atmospheric pressure is lower on
1:49
mountains because there is less air
1:51
above so the weight of the air column is
1:54
smaller. Solved problem question and
1:57
answer. Question. Why is it difficult to
2:00
cook food on high mountains? Answer.
2:02
Cooking is difficult on high mountains
2:04
because lower atmospheric pressure
2:06
reduces the boiling point of water. So
2:09
food cooks more slowly.