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Safety and Environment - Protecting Natural Resources

Grade 4CBSE

Review the key concepts, formulae, and examples before starting your quiz.

🔑Concepts

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Natural resources are materials provided by Earth that humans use to survive, such as air, water, soil, minerals, and forests.

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Renewable resources are those that can be replenished naturally over time, like solar energy, wind energy, and H2OH_2O.

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Non-renewable resources are available in limited quantities and take millions of years to form, such as coal, petroleum, and natural gas.

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Pollution is the addition of harmful substances to the environment. Major types include Air, Water, and Soil pollution.

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Plants play a vital role in maintaining the balance of gases by absorbing CO2CO_2 and releasing O2O_2 during photosynthesis.

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The 3 R's of environment protection are Reduce (using less), Reuse (using things again), and Recycle (processing waste into new products).

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Soil erosion is the removal of the top layer of soil by wind or water. Planting trees (afforestation) helps prevent this.

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Conservation of water involves preventing wastage and keeping our H2OH_2O bodies free from industrial chemicals and sewage.

📐Formulae

Total Waste Management=Reduce+Reuse+Recycle\text{Total Waste Management} = \text{Reduce} + \text{Reuse} + \text{Recycle}

Photosynthesis: 6CO2+6H2O→SunlightC6H12O6+6O2\text{Photosynthesis: } 6CO_2 + 6H_2O \xrightarrow{\text{Sunlight}} C_6H_{12}O_6 + 6O_2

Air Quality Index (AQI)∝1Cleanliness of Air\text{Air Quality Index (AQI)} \propto \frac{1}{\text{Cleanliness of Air}}

💡Examples

Problem 1:

If a factory releases large amounts of CO2CO_2 and smoke into the atmosphere, what kind of pollution is it causing and how can we mitigate it?

Solution:

It is causing Air Pollution.

Explanation:

The smoke contains harmful gases like Carbon Dioxide (CO2CO_2) and Carbon Monoxide (COCO). Mitigation can be done by installing filters in factory chimneys and planting more trees to absorb the excess CO2CO_2.

Problem 2:

Classify the following into Renewable and Non-renewable resources: Solar Energy, Coal, Petroleum, Wind.

Solution:

Renewable: Solar Energy, Wind; Non-renewable: Coal, Petroleum.

Explanation:

Solar and Wind are infinite and replenish quickly. Coal and Petroleum take millions of years to form and are depleted once used.

Problem 3:

How does recycling a plastic bottle help the environment?

Solution:

It reduces the demand for new plastic and prevents land/water pollution.

Explanation:

By following the RecycleRecycle principle, we ensure that plastic does not end up in landfills or oceans, where it would otherwise take hundreds of years to decompose.