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
481
Ozone destruction in the upper atmosphere is mainly caused by:
Answer:
Chlorofluorocarbons (CFCs)
CFCs release chlorine that breaks ozone molecules. This weakens the UV shield. Other pollutants are less effective in stratospheric ozone loss.
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482
Which of the following does **not** cause pollution?
Answer:
Solar energy
Solar power is a clean renewable source. Unlike fossil fuels, it produces no harmful emissions. Hence, it is eco-friendly.
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483
The main natural source of water is:
Answer:
Rain
Rainfall replenishes all surface and groundwater sources. Rivers and ponds depend on rainfall. It is the origin of freshwater.
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484
Which of the following is a non-biodegradable waste?
Answer:
Plastics
Plastics persist in nature and resist decomposition. They clog drains and pollute ecosystems. Organic wastes like cow dung decompose quickly.
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485
An example of a renewable resource is:
Answer:
n example of a renewable resource is:
Renewable resources replenish naturally. Water recycles through the hydrological cycle. Fossil fuels are non-renewable and exhaustible.
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486
The most harmful non-biodegradable waste is:
Answer:
Radioactive waste
Radioactive substances remain hazardous for thousands of years. They contaminate soil, water, and air. Plastics are harmful too but less persistent compared to radiation.
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487
Acid rain is primarily due to:
Answer:
Oxides of sulphur
Burning coal and oil releases sulphur oxides. These combine with water to form acids. It is the main cause of acid rain.
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488
Which of the following does **not** cause soil erosion?
Answer:
Sun
Erosion is caused by moving agents like water, wind, and animals. The sun affects evaporation but not erosion directly. Hence it is not an erosive agent.
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489
Which of the following are air pollutants?
Answer:
re air pollutants?
Aerosols and particulate matter pollute the air. Sewage and fertilizers mostly affect water and soil. DDT is a pesticide contaminant.
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490
The first international Earth Summit was held at:
Answer:
Rio de Janeiro
The 1992 Rio Summit was a milestone. It produced Agenda 21 and climate agreements. It raised global environmental cooperation.
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