Test Index

UPTET Paper 1 2013 Solved Paper

Question : 139 of 150

Marks: +1, -0

Name the lowest layer of the atmosphere.

Solution:

Concept:

The atmosphere is divided into layers based on temperature. The lowest layer, closest to Earth's surface, is the troposphere.

Explanation:

The Earth's atmosphere has five main layers from bottom to top: troposphere, stratosphere, mesosphere, thermosphere, and exosphere.

The troposphere extends from the ground up to about 8–18 km height. It contains most of the air and weather phenomena.

Above it lies the stratosphere, which holds the ozone layer (ozonosphere). The ionosphere is part of the thermosphere, much higher.

Thus, the lowest layer is clearly the troposphere.

d>12

d>50

d>80

d>700

Layer	Range	Feature
Troposphere	0 to 12 km	The lowest layer of Earth's atmosphere. The troposphere contains roughly 80% of the mass of Earth's atmosphere. It is the layer where most of Earth's weather takes place.
Stratosphere	It contains the ozone layer. Temperature Inversion (temperatures rise with increasing altitude) is seen in this layer. This rise in temperature is caused by the absorption of ultraviolet radiation (UV) radiation from the Sun by the ozone layer.
Mesosphere	It is the coldest place on Earth and has an average temperature of around −85 °C It is also the layer where most meteors burn up upon atmospheric entrance.
Thermosphere	The lower part of the thermosphere, from 80 to 550 kilometres above Earth's surface, contains the ionosphere. Ionosphere is used for Radio Communication. The temperature of the thermosphere gradually increases with height. The International Space Station orbits in this layer, between 350 and 420 km.
Exosphere	The outermost layer of Earth's atmosphere. It contains most of the satellites orbiting Earth.

Thus, the troposphere is the lowest layer of the atmosphere.

Answer:

D. Troposphere

Go to Question:

Prev Question

Next Question