The deflection of winds to the right in the northern hemisphere and to the left in the southern hemisphere is stated as
- A.Ferrel's law
- B.Buys Ballot's law
- C.Hadley's law
- D.Charles's law
Correct answer
Explanation
The correct answer is A, Ferrel's law. It states the deflection produced by the rotation of the earth, the Coriolis effect, which turns every freely moving body to the right of its path in the northern hemisphere and to the left in the southern. The deflection is zero at the equator and increases towards the poles, which is why cyclones do not form very close to the equator.
Option B, Buys Ballot's law, is related but different: it says that if you stand with your back to the wind in the northern hemisphere, low pressure lies to your left and high pressure to your right. Option C is not a law of this kind; Hadley is remembered instead for the Hadley cell of tropical circulation. Option D, Charles's law, belongs to physics and relates the volume of a gas to its temperature at constant pressure.
Read the full article: Atmosphere and Winds: Layers, Pressure Belts and Jet Streams
Practice Questions
View allThe ozone layer, which absorbs ultraviolet radiation, lies in which layer of the atmosphere?
- A.Troposphere
- B.Stratosphere
- C.Mesosphere
- D.Thermosphere
Show answer
Ozone is concentrated in the lower and middle stratosphere, and because it absorbs ultraviolet radiation the temperature of this layer rises with height instead of falling.
Read the full explanation →The normal lapse rate of temperature in the troposphere is about
- A.6.5 degrees Celsius per kilometre
- B.1 degree Celsius per kilometre
- C.10 degrees Celsius per kilometre
- D.0.65 degrees Celsius per kilometre
Show answer
This is the average rate at which air temperature falls as one rises through the troposphere, and it explains why hill stations are cooler than the plains and why high peaks carry snow even in the tropics.
Read the full explanation →Meteors entering the earth's atmosphere burn up mainly in which layer?
- A.Stratosphere
- B.Mesosphere
- C.Thermosphere
- D.Exosphere
Show answer
Although the air there is thin, it is dense enough to heat a body moving at cosmic speed by friction, so most meteors glow and are destroyed in this layer and are seen from the ground as shooting stars.
Read the full explanation →Which gas forms the largest share of dry air by volume?
- A.Oxygen
- B.Nitrogen
- C.Argon
- D.Carbon dioxide
Show answer
It is comparatively inert, so it dilutes oxygen and slows combustion, and it enters living things mainly through the nitrogen cycle in which bacteria fix it in a usable form.
Read the full explanation →The warm and dry local wind known as the snow eater blows over which region?
- A.The eastern slopes of the Rockies in North America
- B.The northern slopes of the Alps in Europe
- C.The eastern slopes of the Andes in Argentina
- D.The northern edge of the Sahara
Show answer
The wind is the Chinook. It descends the leeward slope, is compressed and warmed as it sinks, and can raise the temperature sharply in a few hours; it melts or evaporates the snow cover, which is why herders call it the snow eater and why it is valued for exposing…
Read the full explanation →