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Earth and Space Science - Sustainable Resource Management

Grade 8IB

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

🔑Concepts

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Sustainable development is defined as meeting the needs of the present without compromising the ability of future generations to meet their own needs.

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Natural resources are classified into renewable (e.g., solar, wind, biomass) and non-renewable (e.g., fossil fuels like coal, oil, and natural gas composed of CH4CH_4).

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The Greenhouse Effect involves gases such as carbon dioxide (CO2CO_2), methane (CH4CH_4), and nitrous oxide (N2ON_2O) trapping infrared radiation in the atmosphere.

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The Ecological Footprint measures the biologically productive land and sea area required to provide the resources a population consumes and absorb its CO2CO_2 emissions.

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Life Cycle Assessment (LCA) is a process used to evaluate the environmental impact of a product through its entire life cycle, from raw material extraction to disposal.

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Water management strategies include desalination, rainwater harvesting, and reducing the contamination of H2OH_2O sources by industrial runoff.

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Soil sustainability requires managing pHpH levels and nutrient concentrations (like Nitrogen NN and Phosphorus PP) to prevent land degradation and desertification.

📐Formulae

Energy Efficiency=(Useful Energy OutputTotal Energy Input)×100%\text{Energy Efficiency} = \left( \frac{\text{Useful Energy Output}}{\text{Total Energy Input}} \right) \times 100\%

Resource Life Expectancy=Total Remaining ReservesAnnual Rate of Consumption\text{Resource Life Expectancy} = \frac{\text{Total Remaining Reserves}}{\text{Annual Rate of Consumption}}

Percentage Change in Resource Use=New Value−Old ValueOld Value×100%\text{Percentage Change in Resource Use} = \frac{\text{New Value} - \text{Old Value}}{\text{Old Value}} \times 100\%

Concentration=Mass of SoluteVolume of Solution\text{Concentration} = \frac{\text{Mass of Solute}}{\text{Volume of Solution}}

💡Examples

Problem 1:

A solar panel receives 1200 J1200\text{ J} of solar energy and converts it into 180 J180\text{ J} of electrical energy. Calculate the efficiency of the solar panel.

Solution:

Efficiency=180 J1200 J×100=15%\text{Efficiency} = \frac{180\text{ J}}{1200\text{ J}} \times 100 = 15\%

Explanation:

Efficiency is the ratio of useful energy output to the total energy input. In this case, 15%15\% of the sunlight is successfully converted to electricity, while the rest is lost as heat.

Problem 2:

A specific region has a known reserve of 4.5×1094.5 \times 10^9 tons of coal. If the annual consumption rate is 1.5×1081.5 \times 10^8 tons per year, how many years will the coal reserves last?

Solution:

Years Remaining=4.5×1091.5×108=30 years\text{Years Remaining} = \frac{4.5 \times 10^9}{1.5 \times 10^8} = 30\text{ years}

Explanation:

By dividing the total quantity of the non-renewable resource by the rate at which it is used annually, we determine the depletion timeframe.