Tag: evs

Questions Related to evs

Which region of Africa was most involved in drought?

  1. Somalia

  2. Ethiopia

  3. Sahel Regions

  4. Eritrea


Correct Option: C

Which of the following play a very important role in causing rainfall ?

  1. Animals

  2. Plants

  3. Factories

  4. Vehicles


Correct Option: B
Explanation:

Transpiration in plants plays a vital role in the water cycle. The plants transpire and lose water in the form of gases from its aerial parts which increases the moisture content in the atmospheric air. So, the air gets saturated with moisture at a faster rate and causes rainfall. Thus, the correct answer is option B.

Which of the following functions performed by a forest help most in controlling drought?

  1. Forests prevent soil erosion

  2. Forests bring rainfall

  3. Forest have lot of water plants

  4. Both A and B


Correct Option: D

Rain fall patterns depend on 

  1. the underground water table

  2. The number of water bodies in an area

  3. The density of human population in an area

  4. The prevailing season in an area


Correct Option: B
Explanation:

More the number of water bodies in an area more is evaporation of water in that area. As a result, more clouds are formed and there is an increase in rainfall in that area.

So, option B" The number of water bodies in an area" is the correct answer. Rainfall pattern depends on water bodies in that area.

Transfer of heat within water is by

  1. Conduction

  2. Convection

  3. Radiation

  4. None of the above


Correct Option: B
Explanation:

The water is a poor conductors of heat so do not heated by conduction.  When water is heated, the water became lighter. Hot water rises up. The cold water from the sides moves  down towards the source of heat. This water also gets hot and rises and water from the sides moves down.  This process continues till the whole water gets heated. This mode of heat transfer is known as convection.

So, the correct answer is 'Convection'.

Identify the man made calamities.

  1. Flood

  2. Earthquake

  3. Tornado

  4. Global warming


Correct Option: D

Deforestation and pollution are the main causes of drought.

  1. True

  2. False


Correct Option: A

The forest fire is a man made calamity whereas fire is a natural calamity.

  1. True

  2. False


Correct Option: B

Biochemical Oxygen Demand (BOD) in a river water :

  1. Increases when sewage gets mixed with river water

  2. Remains unchanged when algal bloom occurs

  3. has no relationship with concentration of oxygen in the water

  4. Gives a measure of Salmonella in the water


Correct Option: A

What happens when rain falls on soil without vegetational cover?

  1. Rain water percolates in soil efficiently

  2. Rain water causes loss of surface soil

  3. Rain water leads to fertility of the soil

  4. Rain water does not cause any change in soil


Correct Option: B
Explanation:

Vegetation cover on the ground helps to hold the soil in place. It also helps in percolating water into the deeper layers of the soil. The absence of vegetational cover may lead to soil erosion.

So, the correct answer is option B.