Olympiad Test Level 1: Environment and its Conservation - 2 - Class 4 MCQ

Cow Dung is considered as the chief raw material for bio-gas plants. It is because cow dung has high content of nitrogen and gives high-yield of biogas.

Fossil fuels and metallic minerals come in the category of nonrenewable resource, as they cannot be formed in a short span of time. They were created under high pressure and temperature by decomposing decayed plants and animals, millions of years ago.

Natural resources are classified into 2 categories (renewable and non-renewable). Renewable resources can be replenished either naturally or through some recurring processes. Whereas, non-renewable resources cannot be replenished in a short span of time.

Air is utilized for generation of wind energy. As wind provides mechanical power to turbines and convert the energy into electrical energy.

Sunlight produces solar energy. The heat of the sun is harnessed to produce energy. For example, Solar energy is used in Solar cooker for cooking food.

Wind is used as a renewable resource. The energy from the wind is harnessed to turn wind turbines and generators, which generate electricity.

Fossil fuels are remains of organisms which were buried deep under the Earth’s crust and were made of decomposed plants and animals.

Coal is obtained by mining. Large machines are used to remove the layers of soil and expose coal. 

Earth’s temperature increases because of global warming. The various human activities like burning of fossil fuels, cutting down of forests, etc. have resulted in increased greenhouse gases. Thereby, affecting Earth’s temperature.

Global warming causes changes in climate because of changing Earth’s temperature.

Air pollution causes global warming. Release of oxides of carbon and other pollutants in atmosphere causes global warming.

Soil pollution is also known as land pollution. It is caused by improper disposal of waste, use of chemical fertilizers and pesticides, etc.

Continental regions have cold winters. These regions experience snow storms, strong winds and temperature drops.

Industrial waste causes water pollution as all the waste is dumped in water bodies effecting the marine life. Mining activities cause soil erosion, contamination of underground water, air pollution, etc.

We breathe in oxygen and breathe out carbon dioxide. Plants breathe in carbon dioxide and breathe out oxygen during the process of photosynthesis.