1. Top soil contains-
(a) Humus & soil particles
(b) Humus, living organisms & plants
(c) Humus & living organisms
(d) Humus, living organisms & soil particles
S1. Ans.(d)
2. The kind of soil water most useful to plants is
(a) Distilled water
(b) Capillary water
(c) Gravitational water
(d) Hygroscopic
S2. Ans.(b)
3. Wind causes weathering of rocks through
(a) Abrasion
(b) Chemical changes
(c) Frost action
(d) Mechanical forces
S3. Ans.(a)
4. Which of the following has the smallest soil particles?
(a) Sand
(b) Silt
(c) Loam
(d) Clay
S4. Ans.(d)
5. Rise in temperature of water due to addition of hot water into it is known as
(a) Air pollution
(b) Water pollution
(c) Thermal pollution
(d) Soil pollution
S5. Ans.(c)
6. If there were no atmosphere surround the earth, then the temperature of the earth will-
(a) Increases
(b) Increases during day decreases during night
(c) Remains unaffected
(d) Decreases
S6. Ans.(b)
7. The two forms of oxygen found in the atmosphere are-
(a) Water & oxygen
(b) Ozone & oxygen
(c) Water & carbon-dioxide
(d) Water & ozone
S7. Ans.(b)
8. Which of the following is a non-biodegradable pollutant?
(a) Plastic
(b) Fruits and vegetables
(c) Mud
(d) Leaves
S8. Ans.(a)
9. Find the incorrect statement ?
(a) 60% of the global greenhouse effect is due to CO2.
(b) Ozone is highly poisonous to living things.
(c) Bacillus ramous causes ammonification
(d) All biochemical reactions occur in the medium of alcohol
S9. Ans.(d)
10. Which of the following measures can be taken to reduce the wastage of energy?
(a) Preparation of smokeless stoves
(b) Growing fuel wood trees
(c) Use of biogas
(d) All of these
S10. Ans.(d)
