The question asks to identify the type of weather systems that develop in the mid and high latitudes, specifically beyond the tropics. We need to recall the definitions and characteristics of different atmospheric circulation systems.
Correct Option: A) Extra-tropical (or middle latitude) cyclones are large-scale weather systems that form in the mid and high latitudes (typically between 30° and 60° N/S). They are characterized by fronts and are responsible for much of the day-to-day weather changes in these regions.
The question asks to distinguish extra-tropical cyclones from tropical cyclones based on NCERT definitions. We need to evaluate each option against the characteristics of both types of cyclones as described in standard geographical texts.
B) Extra-tropical cyclones have a clear frontal system, which is absent in tropical cyclones. This is a fundamental difference between the two types of cyclones. Extra-tropical cyclones are characterized by the presence of warm, cold, and occluded fronts, which are integral to their formation and structure. Tropical cyclones, conversely, are non-frontal systems.
The question asks about the formation location of extra-tropical cyclones according to NCERT. This requires knowledge of atmospheric circulation patterns and cyclone genesis as described in standard geography textbooks.
Correct Option: B) The polar front is the region where cold polar air masses meet warm tropical air masses, creating a zone of atmospheric instability that is conducive to the formation of extra-tropical cyclones. This is a fundamental concept taught in NCERT geography.
The question describes a specific stage in the life cycle of an extra-tropical cyclone, focusing on the interaction between its cold and warm fronts. Understanding the definitions of different types of fronts is key to answering this question.
C) Occluded. An occluded front forms when a faster-moving cold front catches up to and overtakes a slower-moving warm front. As the cold air mass behind the cold front meets the cooler air mass ahead of the warm front, the warmer air that was originally between them is lifted off the ground. This process leads to the dissipation of the cyclone.
The question asks for the best definition of an earthquake. We need to evaluate each option based on the scientific understanding of what an earthquake is and eliminate those that describe different geological or atmospheric phenomena.
Correct Option: D) A sudden release of stored energy in the Earth's crust causing shaking of the ground
This definition perfectly describes an earthquake. Earthquakes occur when stress builds up along faults in the Earth's crust. When this stress exceeds the strength of the rocks, they rupture, and the stored elastic energy is suddenly released as seismic waves, leading to ground shaking.
The question asks for the specific term used to describe the point inside the Earth where an earthquake originates. This is a fundamental concept in seismology.
Correct Option: B) The point inside the Earth where an earthquake originates is called the Focus. It is also commonly referred to as the Hypocentre. This is the exact location where the seismic rupture begins and seismic waves radiate outwards.