Tectonic plates play a key role in shaping the Earth's surface, with various geological features such as - mountains, trenches, plateaus, etc. Classification of plate boundaries: 1. Constructive Plate Boundaries - Here two plates move away from each other, leading to the rise of magma from the mantlRead more
Tectonic plates play a key role in shaping the Earth’s surface, with various geological features such as – mountains, trenches, plateaus, etc.
Classification of plate boundaries:
1. Constructive Plate Boundaries – Here two plates move away from each other, leading to the rise of magma from the mantle and solidifying to form new crust like- mid-oceanic ridges, rift valleys, etc. E.g. – mid-Atlantic ridge.
The upwelling of magma when the plates move apart leads to volcanism. Very low intensity earthquake occurs here when plates move apart.
2. Destructive Plate Boundaries– Here two plates move towards each other, leading to a collision when the denser plate is subducted below the lighter one. E.g.- the Himalayas formation.
Due to immense pressure and friction strong earthquakes are associated with destructive plates. Volcanism also can occur when the subducted plates melt to form magma and rise up.
3. Conservative plates Boundaries- In this case, the plates move past each other horizontally neither creating nor destroying. E.g.- the San Andreas fault in California.
The energy released by the sliding motions of plates can cause the ground to shake leading to massive earthquakes. As there is no subduction or release of magma no volcanic activity takes place here.
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There are many different types of stars in the sky, classified based on their size,temperature,brightness and lifespan. 1. Main Sequence Stars: These are the most common type, fusing hydrogen into helium in their cores. They are divided into: O-type (blue, massive, and extremely hot) B-type (blue, hRead more
There are many different types of stars in the sky, classified based on their size,temperature,brightness and lifespan.
1. Main Sequence Stars: These are the most common type, fusing hydrogen into helium in their cores. They are divided into:
O-type (blue, massive, and extremely hot)
B-type (blue, hot, and luminous)
A-type (white, hot, and bright)
F-type (yellow-white, moderately hot)
G-type (yellow, like the Sun)
K-type (orange, cooler)
M-type (red, coolest and most common)
2. Red Giant Stars:
Cool, luminous stars that have exhausted their hydrogen fuel and expanded.
3. White Dwarf Stars:
Hot, compact remnants of stars that have shed their outer layers.
4. Neutron Stars:
Extremely dense, spinning stars formed from supernovae explosions.
5. Black Holes:
Regions of spacetime where gravity is so strong, not even light escapes.
6. Brown Dwarfs:
Objects that don’t quite meet the criteria for stars, as they don’t sustain nuclear fusion.
7. Variable Stars: Stars that change brightness, including:
Cepheid Variables (pulsating, used for distance measurement)
RR Lyrae Variables (pulsating, used for distance measurement)
Delta Scuti Variables (pulsating, rapid changes)
Mira Variables (long-period, pulsating)
8. Binary and Multiple Star Systems: Stars that orbit each other, including:
– Visual Binaries (visible with a telescope)
– Spectroscopic Binaries (detected by spectral changes)
– Eclipsing Binaries (stars pass in front of each other)
9. Supergiant Stars:
Extremely large, luminous stars, often near the end of their lives.
10. Wolf-Rayet Stars:
Massive, hot stars with strong winds and intense radiation.
In 2024 new discoveries and advancements in astronomy may lead to further divisions or reclassifications of star types.
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