General Science/Everyday Science MCQs
Topic Notes: General Science/Everyday Science
MCQs and preparation resources for competitive exams, covering important concepts, past papers, and detailed explanations.
Plato
- Biography: Ancient Greek philosopher (427–347 BCE), student of Socrates and teacher of Aristotle, founder of the Academy in Athens.
- Important Ideas:
- Theory of Forms
- Philosopher-King
- Ideal State
71
What is humus in soil science?
Answer:
Organic matter from decayed plants and animals
Humus is dark, nutrient-rich material formed by decomposition. It improves soil fertility, water retention, and structure. It is essential for healthy crop growth.
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### Structure and Composition of Earth
72
Which of the following describes clay particles?
Answer:
Very fine and smooth
Clay has the smallest particle size among soil types. Its fine texture allows it to retain water but makes drainage slow. This property makes clay heavy and sticky when wet.
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73
The topmost layer of soil, rich in organic material, is called:
Answer:
Topsoil
Topsoil is the fertile layer where plants grow, rich in nutrients and humus. It supports root systems and biological activity. Farmers focus on preserving it for sustainable agriculture.
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74
Marble is formed through metamorphism of which rock?
Answer:
Limestone
Heat and pressure turn limestone into marble by recrystallizing its calcite. Marble’s fine grain and polishability make it popular for sculpture and architecture. It is often white but can have colored streaks.
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75
Which mineral is a key ingredient for making glass?
Answer:
key ingredient for making glass?
Quartz (silicon dioxide) is melted and processed to produce glass. Its high silica content makes it ideal for transparent and durable products. Glass manufacturing has relied on quartz sand for centuries.
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76
Loamy soil is best suited for which purpose?
Answer:
est suited for which purpose?
Loam is a balanced mix of sand, silt, and clay, with good fertility and water retention. Farmers prefer it because it supports a wide range of crops. Its texture allows both drainage and nutrient storage.
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77
Which element makes up the largest portion of Earth’s crust?
Answer:
Oxygen
Oxygen accounts for about 46% of the crust by weight, mostly bonded with silicon. Silicon and oxygen together form silicate minerals. These compounds dominate Earth’s crustal rocks.
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78
Rocks that form when magma cools and solidifies are known as:
Answer:
Igneous
Igneous rocks crystallize directly from molten material. Granite and basalt are classic examples. Their texture depends on whether they cool quickly on the surface or slowly underground.
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79
The natural breakdown of rocks by weather conditions is called:
Answer:
Weathering
Weathering refers to the breakdown of rocks by temperature, wind, rain, or biological activity. It differs from erosion, which is the movement of particles. Weathering plays a key role in soil formation.
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80
Which of the following is NOT classified as a rock type?
Answer:
Metallic
The three main rock types are igneous, sedimentary, and metamorphic. Metals are elements or alloys, not rock categories. Rocks are defined by their origin and formation processes.
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