Chapter 1: Origin and Structure of the Ear (Set-4)
The concept of accretion in planetary formation explains that planets formed through
A Sudden explosions
B Gradual accumulation of particles
C Volcanic outpouring
D Stellar collision
Accretion theory states that dust and gas particles collided and stuck together under gravity, gradually forming larger bodies that developed into planets over long geological time.
The apparent westward movement of stars across the sky is caused due to Earth’s
A Revolution
B Axial tilt
C Rotation
D Elliptical orbit
Earth’s rotation from west to east makes celestial bodies appear to move westward, producing the daily apparent motion of stars and the Sun.
Which longitude is taken as the basis for Greenwich Mean Time
A 90° East
B 180°
C 0°
D 23½°
Greenwich Mean Time is based on the Prime Meridian at 0° longitude, serving as the global reference for time calculation.
The layer of Earth responsible for volcanic magma generation is mainly the
A Crust
B Upper mantle
C Outer core
D Inner core
Partial melting in the upper mantle produces magma, which rises through the crust and causes volcanic activity at suitable locations.
Which evidence of continental drift is derived from distribution of ancient coal deposits
A Structural similarity
B Paleontological evidence
C Paleoclimatic evidence
D Geophysical evidence
Coal deposits in present cold regions indicate earlier warm climates, supporting the idea that continents shifted from different latitudinal positions.
Plate tectonics considers lithosphere to be divided into
A Climatic zones
B Continents only
C Rigid plates
D Ocean basins
The lithosphere is broken into rigid tectonic plates that move slowly over the asthenosphere, causing earthquakes, volcanoes, and mountain formation.
Which fault type is associated with tensional forces and crustal extension
A Reverse fault
B Thrust fault
C Normal fault
D Strike-slip fault
Normal faults develop when tensional forces pull the crust apart, causing the hanging wall to move downward relative to the footwall.
The intensity of earthquakes is measured using
A Richter scale
B Mercalli scale
C Beaufort scale
D Fujita scale
The Mercalli scale measures earthquake intensity based on observed damage and human experience, rather than energy released.
Which type of igneous rock is formed at mid-ocean ridges
A Granite
B Diorite
C Basalt
D Obsidian
Basalt forms from lava erupting at mid-ocean ridges where sea-floor spreading creates new oceanic crust.
Which sedimentary rock indicates deposition in calm water conditions
A Conglomerate
B Breccia
C Shale
D Sandstone
Shale forms from fine clay particles deposited in low-energy environments like lakes and deep seas, indicating calm conditions.
The transformation of coal into graphite represents
A Contact metamorphism
B Regional metamorphism
C Dynamic metamorphism
D Low-grade metamorphism
Graphite forms from coal under intense heat and pressure over large regions, representing regional metamorphic processes.
The Lehmann discontinuity separates the
A Crust and mantle
B Mantle and outer core
C Outer core and inner core
D Upper and lower mantle
The Lehmann discontinuity marks the boundary between Earth’s liquid outer core and solid inner core, identified through seismic studies.
Which type of volcanic eruption is characterized by quiet lava flows