Topic 4: Unit-1

Question 1

Purpose of gravity in the atmosphere?

Answer 1

It traps gases near the earth’s surface to form the atmosphere

Question 2

How does air react when it moves further away from sea level?

Answer 2

Air gets less dense - the greater the distance from the earth, the thinner the air

Question 3

What is the atmosphere

Answer 3

The layer of gases surrounding the Earth

Question 4

The atmosphere consists of…?

Answer 4

• 78% nitrogen
• 21% oxygen
• 1% all other gases
  (e.g. CO2, water vapour, helium or neon)

Question 5

There are four distinct layers in the atmosphere, i.e…?

Answer 5

• Troposphere (sea level to 10km)
• Stratosphere (10 - 50 km)
• Mesosphere (50 - 80 km)
• Thermosphere (80 - 350 km)

Question 6

Altitude

Answer 6

height above sea level

Question 7

How does air density change with altitude?

Answer 7

Air density decreases as altitude increases, meaning the higher you go, the thinner the air becomes.

Question 8

What is the temperature gradient?

Answer 8

It’s the rate of change in temperature with altitude. In some layers, temperature drops rapidly, while in others, it rises or remains constant.

Question 9

What is atmospheric pressure?

Answer 9

The weight of the air pressing down on the Earth’s surface, which decreases as you go higher in altitude.

Question 10

How does atmospheric pressure change with altitude?

Answer 10

Atmospheric pressure decreases with altitude because there are fewer air molecules at higher elevations.

Question 11

What happens to temperature at the boundary of different layers?

Answer 11

Temperature usually changes direction (increases or decreases) at the boundaries between layers, marking transitions like the tropopause and stratopause.