GRADE 9 VACATION HOME WORK SHEET - 1

1. State Archimedes Principle? [2]
2. What is the upthrust experienced by a cube of edge – length 5cm made of iron when completely immersed in ethanol of density 0.8 g/cm3 [3]
3. If cross – sectional area of an object is more than the pressure applied by the external force is :-
(a) Less (b) More (c) Remains same (d) None of the above. [1]
4. Units of Relative Density are :-
(a) Kg/m3 (c) Depends on the density of the substance (b) Unit less (d) Depend on the density of water [1]
5. Pressure at a point in the liquid is (a) Same in all directions (b) Greater in the upward direction (c) Grater in the downward direction (d) None of the Above [1]
6. If the area of an object is less then the pressure acting on that object will be (a) Less (b) More (c) Independent of area (d) None of the above [1]
7. Define Pressure? How is thrust different from Pressure? [2]
8. What are fluids? What are the factors on which the upward pressure at a point on a fluid depends? [2]
9. Define density and relative density? [2]
10. Calculate the pressure at a depth of 50m below the surface of sea. The density of sea water is 1024 Kg/m3. [2]
11. What makes a body to float or sink in a liquid? [3]
12. A block of wood tied to the bottom of water tank as shown. The wooden block exerts tension, on the wire tied to it. The dimension of the block are 20cm × 20cm × 40cm. The density of the wood is 600Kg/m3. What is the tension in the wire? [3]
              I               I -----> BLOCK OF WOOD
              I               I
              I_______ I
                    I_I -----------> LEAD ATTACHED TO IT
  
13. The weight of balloon and gas inside it is 12KN. The volume of the balloon is 1200m3. The density of air is 1.26 Kg/m3. Calculate a) the weight it can lift b) the acceleration as it rises. [3]
14. A cylindrical block of wood of height 4.2m and mass 100Kg floats vertically in water. The relative density of wood is 0.8
1) What height of the block will be seen above the water ?
2) If block of lead of mass 10kg is placed, what height of the block will be seen above water? [3]
15. S. I. unite of Pressure :- (a) Nm2 (b) N/m2 (c) Nm (d) N/m [1]
16. What will be the up thrust experienced by a balloon of volume 120m3 filled with hydrogen. The density of air = 1.140 Kg/m3 and density of hydrogen = 0.081Kg/m3 at room temperature. What is the maximum weight this balloon can lift? [3]

GRADE 10 VACATION HOME WORK SHEET - 2

1. Define biodegradable wastes. (1 mark)
2. Define decomposers. Name one decomposer. (1 mark)
3. Which of the following belong to the same trophic level?Tree, Frog, Snake, Grass, Lizard. (1Mark)
4. Name the group of chemical compounds which damages the ozone layer. (1mark)
5. What would happen if all the decomposers were eliminated from the Earth? Explain with reasons.(2 marks)
6. Give an example of a food chain operating in fresh water pond. Mention the food habit of
each trohic level in this food chain. (2 marks)
7. Consider the food chain: Grass -------- Deer------ Lion. What will happen, if lions are removed from the above food chain? (2 marks)
8. In terms of energy, which is at an advantageous position-a vegetarian or a non-vegetarian? Why? (2 marks)
9. With the help of food chain explain how biological magnification of harmful chemicals can occur. (2 marks)
10. What is the difference between the food habits of organism belonging to the forest and third trophic levels? Give example each of organisms belonging to these trophic levels. (2 marks)
11. What is a food chain? Write the food chain operating in a pond. State the food habit of each trophic level in this food chain. (3 marks)
12. Where is ozone layer found in atmosphere? What is its importance? Write the harmful effects
UV rays. (3 marks)
13. A non-biodegradable toxic chemical has entered into the food chain. Which type of food habit
will you suggest to a man, vegetarian or non-vegetarian? Explain with the help of a food
chain. The food chain which you would suggest, is advantageous in an another aspect. How?
(5 marks)
14.Name the process by which the volume of solid wastes can be reduced. (1 mark)
15. What is meant by non-biodegradable waste materials? (1 mark)
16. Why are plants called producers? (1 mark)
17. Which of the following belong to the same tropic level? Goat, Spider, Plants, Hawk, Rat. (1 mark)
18. State two causes and two effects of the depletion of ozone layer in the atmosphere. (2 marks)
19. How non-bio degradable substances would affect the environment. (2 marks)
20. Given below is a food chain Grass----- Grasshopper ------- Frog---- Snake ------ Peacock
What will happen to the member of different trophic level in the food chain, if all the frogs of
that area are removed? (2 marks)
21. How do food chains get shortened? How does their shortening affect the biosphere? (2 marks)
22. The following are the organisms found in the grass land. Construct a food chain with four trophic levels. Seed eating birds, Grass hopper, Lion, Green plants, Rat, Deer, Frog, Snake. (2 marks)
23. Consider the following food chains (3 marks) Grass --- Mice --- Snakes ---- Peacocks
If in this chain, 100 J of energy is available at the producer level, then calculate the energy
transferred to the peacocks as food. State the law used in calculations.
24. What is ten per cent law? Explain with an example how energy flows through different
trophic levels. (3 marks)
25. What is ozone layer? Write about its importance. Which radiations are absorbed by ozone
layer? What are the causes of the depletion of ozone layer? Which diseases are likely to be
caused if the ozone layer become thinner?
26. What would happen if the ozone layer in the atmosphere completely disappears? (1 mark)
27. Name two waste materials which can be recycled? (1 mark)
28. Write the full name of DDT. (1mark)
29. Give the names of two non-biodegradable wastes which pollute our environment. (1mark)
30. What is the difference between a food chain and a food wed? (2 marks)
31. What is the difference between the food habits of organisms belonging to second and fourth
trophic levels? Give example each of organisms belonging to these trophic levels. (2 marks)
32. Which food chains are advantageous in terms of energy? Support your answer giving one
example. (2 marks)
33. How biodegradable substances would affect the environment. (2 marks)
34. What is biological magnification? Will the levels of this magnification be different at different
levels of the ecosystem? (2 marks)
35. Why are some substance biodegradable and some non-biodegradable? (2 marks)
36. What is a food chain? How does study of food chain in an area or habitat help us? Give an
example of four-step food chain operating in a large lake. (3 marks)
37. Consider the following food chains:
(a) Plants ------- Mice------ Snakes----- Hawks
(b) Plants------- Mice------- Hawks
If energy is available at the producer level in both the food chains is 100 J, in which case will
hawks get more energy as food and by how much? Justify your answer. (3 marks)
38. What is garbage? What does garbage consists of? How would you dispose the following
wastes?
(i) Domestic wastes like vegetable peels
(ii) Industrial wastes like metallic cans
(iii) Plastic material. (5 marks)
39.What is the ultimate source of energy for organisms? (1mark)
40. What are the various steps of food chain called? (1mark)
41. How is ozone formed? (1mark)
42. What are omnivores? Give one example. (1mark)
43. Define an ecosystem. (1mark)
44. How biodegradable substances would affect the environment. (2marks)
45. How non-biodegradable substances would effect the environment. (2marks)
46. What will happen if we kill all the organisms in one trophic level? (2marks)
47. What is biological magnification? Will the levels of this magnification be different at different
levels of the ecosystem? (2marks)
48. What are the problems caused by the non-biodegradable wastes that we generate? (2 marks)
49. What is the role of decomposers in the ecosystem? (3marks)
50. (a) What are ‘Ecological Pyramids’? Draw an ecological pyramid having four trophic
levels with snake as one of its components.
(b) The number of malaria patients in a village increased tremendously when large
number of frogs were exported from the village. What could be the cause for it?
Explain with the help of a food chain. (5 marks)
51.Give an example of a four step food chain operating in grassland. Name the secondary
consumer in this food chain. (1mark)
52. What are ecological pyramids? (1mark)
53. Write the full form of CFC. (1mark)
54. Name the process by which the volume of solid wastes can be reduced. (1mark)
55. Give two harmful effects of UV radiation. (1mark)
56. Why is damage to the ozone layer a cause for concern? What steps are being taken to limit
this damage? (2 marks)
57. What is meant by non-biodegradable waste material? Give its two examples. (2marks)
58. How does recycling of matter or waste materials help in ecological balance? (2marks)
59. What are CFC’s? What harm do they cause? (2 marks)
60. What will happen if all the deer are removed from the earth? (2marks)
61. Distinguish between the autotrophs and decomposers. (2 marks)
62. Differentiate between biodegradable and non-biodegradable substances. (3marks)
63. How is recycling of waste materials help in maintaining ecological balance? (3marks)
64. State and explain the 10 per cent law. (3marks)
65. What is ozone layer? Write about its importance. Which radiations are absorbed by ozone
layer? What are the causes of the depletion of ozone layer? Which diseases are likely to be
caused if the ozone layer become thinner? (5 marks)

GRADE 10 VACATION HOME WORK SHEET -1

1. Define afforestation. [1]
2. Why coal is called fossil fuel? [1]
3. Why is fuel oil better than coal for industrial use? [2]
4. Why is water necessary for living organisms? [2]
5. What are the reasons for conservation of forest and wildlife? [2]
6. Mention the disadvantages of dams. [2]
7. What are the effects of deforestation? [3]
8. What is meant by water table? Why is it important? [3]
9. What are the benefits of water harvesting? [3]
10. Name the stakeholders of forests. [3]
11. Define recycling. Give one example. [1]
12. Who was Amrita devi? [1]
13. Why has it become necessary to look for inexhaustible energy sources? [2]
14. What is the difference between exhaustible and inexhaustible natural resources?[2]
15. Name four modes of traditional water harvesting at the community level. [2]
16. What is the advantage of exploiting resources with short term aim? [2]
17. How are water resources managed and consumed? [3]
18. Write any three steps that you would take for sustainable development of the environment.[3]
19. What are different ways to reduce consumption of the various natural resources?[3]
20. What are the problems faced by construction of large dams? [3]
21. What is rain water harvesting? [1]
22. Define a resource. [1]
23. Why wildlife is important to us? [2]
24. What is difference between deforestation and afforestation? [2]
25. Name four alternatives to mega projects like dams. [2]
26. What do you meant by conservation management? [2]
27. List three things which increase pressure on our natural resources. [3]
28. What are the factors to check the quality of water? [3]
29. What changes can you make in your habits to become more environments friendly?[3]
30. What are results of chipko movement? [3]
31. Mention one major effect due to deforestation? [1]
32. Name two fossil fuels. [1]
33. What are the disadvantages of using coal and petroleum? [2]
34. What is GAP? Explain. [2]
35. Write steps to conserve energy. [2]
36. Mention two causes of over- exploitation of natural resources. [2]
37. Explain in detail the three R’s in the process of saving the environment. [3]
38. What are the benefits of water harvesting? [3]
39. Why there should be equitable distribution of our resources? What forces would be working against an equitable distribution of our resources. [3]
40. With the help of an example explain how participation of local people is useful for conservation of forest. [3]
41. 1. What is biodiversity? (1mark)
42. Define silviculture. (1mark)
43. What is Ganga Action Plan? (1mark)
44. What do you mean by water harvesting? (1mark)
45. What is the need of managing our resources? (2marks)
46. Explain social problems associated with the construction of dams. (2marks)
47. What are various advantages of water stored in the ground? (2 marks)
48. What is meant by global warming? (2 marks)
49. Can you suggest some changes in your school which would make it environment friendly?Suggest atleast three changes. (3marks)
50. State the advantages of constructing dams across the rivers. (3marks)
51. What are the methods adopted for retention of water? (3marks)
52. What steps should be taken for the conservation of wild life? (5marks)
53. Write the steps which can be taken to conserve energy resources like coal and petroleum.(5marks)

GRADE 10 CHAPTER 15 HOME WORK SHEET - 1

1.      Define: (a) Biodegradable materials (b) Non-biodegradable materials (c) eco-system

2.      Why are some substances biodegradable and some non-biodegradable?

3.      Give any two ways by which biodegradable substances would affect the environment.

4.      Give any two ways by which non-biodegradable substances would affect the environment.

5.      Give an example of an eco-system of pond.

6.      What is food chain? Give an example of detritus food chain.

7.      What is food web? Give an example of it.

8.      What is the role of decomposers in an eco-system?

9.      What are tropic levels? Give an example of food chain and state the different tropical levels in it.

10.  What do you understand by unidirectional flow of energy?