Consider the following statements about ‘Biochemical Oxygen Demand’ (BOD):
1. It is the amount of oxygen required by bacteria to break down the organic matter present in a certain volume of a sample of water.
2. Highly polluted water have BOD value of less than 5 ppm.
Which of the statements given above is/are correct?
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If an opaque object on the path of light becomes very small, light has a tendency to bend around it and not walk in a straight line. This effect is known as:
The presence of certain minerals is essential in water, however, if found in excess they can be harmful to our body. In this context, which of the following statements are correct?
1. Deficiency of fluoride in drinking water causes diseases such as tooth decay.
2. Excessive sulphate in drinking water causes laxative effect.
3. Excess lead in drinking water can cause disease such as ‘blue baby’ syndrome.
Select the correct answer using the code given below.
Consider the following statements about ‘Photochemical Smog’:
1. It is a phenomenon of cool humid climate.
2. It occurs when sunlight acts on unburnt hydrocarbons and nitrogen oxides.
3. Ozone in photochemical smog is responsible for the haze.
Which of the statements given above is/are correct?
Consider the following statements about the ‘scattering of light’:
1. Very fine particles scatter mainly blue light while particles of larger size scatter light of longer wavelengths.
2. If the size of the scattering particles is large enough, then, the scattered light may even appear white.
Which of the statements given above is/are correct?
Read the following statements carefully in the context of ‘particulate pollutants’?
1. Smoke particulates consist of gaseous or mixture of gaseous and liquid particles formed during combustion of organic matter.
2. Dust is composed of fine solid particles produced during crushing, grinding and attribution of solid materials.
3. Mists are produced by particles of spray liquids and by condensation of vapours in air.
4. Fumes are generally obtained by the condensation of vapours during sublimation, and boiling.
Which of the statements given above are correct?
Consider the following statements:
1. The e-Gopala App is a comprehensive breed improvement marketplace and information portal, directly used by farmers.
2. Web version of e-GOPALA has been developed by the Union Ministry of Fisheries, Animal Husbandry and Dairying.
Which of the statement(s) given above is/are correct?
The use of an electric fuse protects the electric circuit and the appliances from a possible damage by
Consider the following statements about ‘Human Body’:
1. Muscles contain special proteins which contract and relax to cause movement.
2. We can control the movement of all the muscles in our body.
Which of the statement(s) given above is/are correct?
If an opaque object on the path of light becomes very small, light has a tendency to bend around it and not walk in a straight line. This effect is known as:
With reference to ‘blood’ present in the human body, consider the following statements:
1. It carries oxygen and food to all the cells in human body.
2. It collects wastes from the cells for disposal.
3. It is a type of connective tissue.
Which of the statements given above is/are correct?