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#### Important Questions

7th Standard EM

Reg.No. :
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Science

Time : 01:00:00 Hrs
Total Marks : 100

#### 2 Marks

81 x 2 = 162
1. Name some of the derived quantities.

2. Give the value of one light year.

3. Write down the formula used to find the volume of a cylinder.

4. Give the formula to find the density of objects.

5. Name the liquid in which an iron ball sinks.

6. Name the units used to measure the distance between celestial objects.

7. What is the density of gold?

8. What is the area of 10 squares each of side of 1 m.

9. Find the area of the following regular shaped figures: (Take $\pi$ = 22/7)
(a) A rectangle whose length is 12 m and breadth is 4 m.
(b) A circle whose radius is 7 m.
(c) A triangle whose base is 6 m and height is 8 m.

10. Find the volume of (Take $\pi$ = 22/7)
i. a cube whose side is 3 cm.
ii. a cylinder whose radius is 3 m and height is 7 m.

11. Write the SI unit of speed

12. What is the fundamental unit of amount of substance?

13. What is the SI unit of electric charge?

14. How do you find the area of irregularly shaped figures?

15. How will you determine the volume of a liquid?

16. Which one of the following has more volume. Iron block or a wooden block of same mass.

17. Which one of the following has more density. Water or cooking oil.

18. What is the distance between the earth and proxima centauri star?

19. All objects having uniform speed need not have uniform velocity. Describe with the help of examples.

20. “She moves at a constant speed in a constant direction”. Rephrase the same sentence in fewer words using concepts related to motion.

21. Correct your friend who says “The acceleration gives the idea of how fast the position changes”.

22. Is displacement a scalar quantity?

23. Give some examples for scalar quantity

24. Mention any two conditions for stability of a body?

25. Write the chemical formula and name the elements present in the following compounds:
a. Sodium chloride
b. Potassium hydroxide
c. Carbon-di-oxide
d. Calcium oxide
e. Sulphur dioxide

26. Classify the following molecules as the molecules of element or compound

27. What do you understand by chemical formula of a compound? What is its significance?

28. Write the symbols for the following elements and classify them as solid, liquid and gas
Aluminum, carbon, chlorine, mercury, hydrogen and helium

29. Classify the following as elements and compounds
Water, common salt, sugar, carbon dioxide, iodine and lithium

30. How many elements are known at present?

31. What is a molecule?

32. What is the atomicity of H2SO4?

33. Define an atom.

34. Name the sub-atomic particles.

35. What is the characteristics of proton?

36. What is a neutron?

37. What is the mass of a proton?

38. What is isotone?

39. In the notation of an atom ZXA. What does A & Z represent?

40. Write two types of reproduction in plants.

41. Define – pollination.

42. What are the agents of pollination?

43. What is tendril?

44. What is tendril?

45. Describe a stamen.

46. Name the sub aerial modifications of stem.

48. What are breathing Roots or Pneumatophores?

49. Write about the right way of protect the eyes?

50. How to keep your hair clean and healthy?

51. Sobi frequently playing with her mobile. Suggest your ideas to protect his eye from irritation?

52. Ravi said “Ganga had minor burn, so I washed with water” Do you agree with his statement or not? Explain Why?

53. List two measures to maintain community hygiene

54. Name two disease which can be prevented by vaccination.

55. What is Raster Graphics?

56. Write notes on 2D and 3D pictures

57. What is 'Photoshop'?

58. Name the types of pictures?

59. Temperature of Srinagar (J&K) is — 40C and in Kodaikanal is 30C which of them has greater temperature? What is the difference between the temperatures of these two places?

60. Jyothi was prepared to measure the temperature of hot water with a clinical thermometer. Is it right or wrong? Why?

61. A clinical thermometer is not used to measure the temperature of air, why?

62. What is the use of kink in clinical thermometer?

63. What is the S.I unit of electrical conductivity?

64. Define fuse.

65. Name some devices that run using heat effect of electric current

66. What is a battery?

67. State two examples of periodic changes.

68. Cold milk is heated and it becomes hot. Which type of change it is?

69. Growing of nails is a periodic change. Why?

70. What type of energy changes is associated when ice melts?

71. Which organelle uses energy from sunlight to make starch?

72. What are the main things in a nucleus?

73. What does cell membrane do?

74. Why lysosomes are known as scavengers of the cell?

75. Define – dichotomous key

76. Write two examples of Monera.

77. What is binomial nomenclature?

78. Write the binomial name of a) Human being b) Paddy

79. What is the Shortcut key for Save option?

80. What is Tux Math?

81. What is the use of Ranger ?

82. #### 3 Marks

87 x 3 = 261
83. What are derived quantities?

84. Define the density of objects.

85. What is one light year?

86. Define -one astronomical unit?

87. A solid cylinder of mass 280 kg has a volume of 4 m3. Find the density of cylinder.

88. Define mass Mention its unit.

89. What is physical quantity? give example.

90. What do you mean by 'unit'?

91. What is measurement?

92. What is meant by area?

93. What is capacity of a container?

94. What is the relation between density, volume and mass?

95. Define astronomical unit

96. Define one light year.

97. Wooden block occupies more volume than the iron ball of same mass. Give reason.

98. Show the shape of the distance – time graph for the motion in the following cases.
a. A bus moving with a constant speed.
b. A car parked on a road side.

99. What do you mean by constant acceleration?

100. What is centre of gravity ?

101. A body moves is a circle of radius '2R' what is the distance covered and displacement of the body after 2 complete rounds?

102. Draw distance-time graphs for the following
(i) a stationary body
(ii) a body moving with variable velocity.

103. Mention the real life applications of centre of gravity.

104. Explain the concept which is used in the continuous movement of Thanjavur doll?

105. Write note on the following:
(i) Nautical mile
(ii) knot.

106. Saranya jogs from one end A to the other end B of a straight road of length 320m in 2min 40 seconds. Then she turns back and jogs 100m to point C in 1 min. what is her average velocity in jogging.

107. A train starting from a railway station and moving with uniform acceleration attains a speed of 40 km/h in 10 minutes. Find its acceleration?

108. Define speed Mention its formula and unit.

109. What is non-uniform velocity? Give example

110. What is stability? Mention its types.

111. Write the chemical formula for the following elements
a. Hydrogen
b. Nitrogen
c. Ozone
d. Sulphur

112. What are compounds? Give two examples

113. Give an example for the elements derived from their Latin names

114. What is atomicity of elements?

115. Calculate the atomicity of H2SO4.

116. Aakash noticed that the metal latch on gate was difficult to open during hot sunny days. However, this same latch was not difficult to open at night. Aakash observed that the latch and the gate are exposed to the sun during the day.
a. Formulate a hypothesis based on the information provided.
b. Briefly state how you would test the hypothesis stated in (a).

117. What changes take place in the movement and arrangement of particles during heating process?

118. In the diagram below, the circle, square and triangle represent the atoms of different elements.

In the diagram above, identify all combinations that represent
a. A molecule of a compound
b. A molecule of an element consisting of two atoms
c. A molecule of an element consisting of three atoms

119. What is an atom?

120. What are the 3 most abundant atoms on the earth?

121. Give an account of elements known to us

122. What are metalloids? Give examples

123. Give an example of a metal which
(a) is liquid at room temperature.
(b) is the best conductor of heat.

124. Write any two properties of a compound.

125. What happens to matter during heating?

126. How do hot air balloons float?

127. Why is hydrogen considered as an element?

128. Write the difference between a mixture and compund.

129. Distinguish Isotopes from Isobar.

130. Differentiate mass number from atomic number.

131. An atom of an element has no electron, will that atom have any mass or not? Can atom exist without electron? If so then give example.

132. Is the structure of the atom the same as the structure of the solar system

133. Draw the atomic structure of Oxygen

134. What is atomic mass number. Mention its formula?

135. Define isotopes? Give example.

136. Define Isobars? Give example

137. What are the limitations of Thomson's model of an atom?

138. From the symbol 15P31, state.
(i) Mass number of phosphorus.
(ii) Atomic number of phosphorus.

139. What makes atoms stick together?

140. Write notes on phyllode.

141. Ginger is considered to be a stem, not a root. Why?

142. Write a note an roots modified for mechanical support.

143. How do Epiphytic roots differ from Sucking roots?

144. Write a note on phylloclade.

145. What are traps or Insectivorous plants?

146. Differentiate self pollination and cross pollination

147. Identify the plant and the modification seen in it.

148. Parasitic plants lack leaves

149. Why do all plants lack breathing roots?

150. Why the first aid is essential?

151. A person is sleeping during day time. Why does this happen with some people that they feel sleepy during day time in office or in the classroom. Have you ever come across such situation? Explain.

152. Write a note on non-communicable diseases.

153. Write a note on Chicken pox.

154. We should use a handkarchief when we sneeze, Justify.

155. What can we do to maintain personal hygiene?

156. Richa had a pet dog. She vaccinated him regularly. He suddenly bit a stranger. Do you think that the person could have got Rabies.

157. Differentiate between Raster and Vector

158. Why do we use Mercury in thermometers?Can water be used instead of mercury?What are the problems in using it?

159. Swathi kept a laboratory thermometer in hot water for some time and took it out to read the temperature. Ramani said it was a wrong way of measuring temperature. Do you agree with Ramani? Explain your answer.

160. Define an electric current.

161. Differentiate parallel and serial circuits.

162. Distinguish physical and chemical changes.

163. How can a change occur in a substance?

164. What is the difference between dissolution of sugar and burning of sugar?

165. Distinguish between the following pairs Smooth ER and Rough ER Cell wall and cell membrane Chloroplast and mitochondria

166. Write correct sequence from cell to organism?

167. Classify the following terms into cells, tissues, organs and write in the tabular column given below
Neuron, Lungs. Xylem, brain, adipose, Leaf, RBC, WBC, hand, muscle, heart, ovum, squamous, phloem, cartilage.

 Cell Tissue organ
168. Write the levels of classification.

169. Write any two merits of Five Kingdom classification.

170. #### 5 Marks

44 x 5 = 220
171. Describe the graphical method to find the area of an irregularly shaped plane figure.

172. How will you determine the density of a stone using a measuring jar?

173. How will you find the volume of an irregularly shaped object (stone) by using measuring cylinder?

174. How will you find the area of irregular objects?

175. Explain the types of stability with suitable examples.

176. Write about the experiment to find the centre of gravity of the irregularly shaped plate.

177. Write the differences between distance and displacement

178. Draw velocity-time graph for the following data:
1. Bus at rest

 Time / s 0 1 2 3 4 5 Speed / ms-1 0 0 0 0 0 0

2. Bus travelling at uniform speed of m/s

 Time / s 0 1 2 3 4 5 Speed / ms-1 10 10 10 10 10 10

3. Bus travelling at uniform acceleration

 Time / s 0 1 2 3 4 5 Speed / ms-1 10 10 20 30 40 50

4. Bus travelling at uniform deceleration

 Time / s 0 1 2 3 4 5 Speed / ms-1 50 40 30 20 10 0

5. Bus travelling with increasing acceleration
(non - uniform acceleration)

 Time / s 0 1 2 3 4 5 Speed / ms-1 0 2 8 18 32 50
179. The motion of a car is given in the following data draw distance - time graph.
(a) Car at rest

 Time / s 0 1 2 3 4 5 Speed / ms 0 20 20 20 20 20

(b) Car travelling at uniform speed of 10 ms-1

 Time / s 0 1 2 3 4 5 Speed / ms 0 10 20 30 40 50

(c) Car travelling at increasing speed

 Time / s 0 1 2 3 4 5 Speed / ms 0 5 20 45 80 125

(d) Car travelling at decreasing speed

 Time / s 0 1 2 3 4 5 Speed / ms 0 45 80 105 120 125
180. Differentiate metals and non metals.

181. Explain the characteristics of compounds

182. Differentiate between elements and compounds

183. Write any five characteristics of compound.

184. Write down the properties of metalloids

185. (i) Draw the symbol for some elements as proposed by Dalton.
(ii) What are rules to be followed while assigning symbol to element.

186. Draw the atom structure and explain the position of the sub-atomic particles.

187. The atomic number and the mass number of an element is 26 and 56 respectively. Calculate the number of electrons protons and neutrons in its atom. Draw the structure.

188. What are nucleons. Why are they so called? Write the properties of the nucleons.

189. Define valency? What is the valency of the element with atomic number 8. What is the compound by the element with hydrogen.

190. What was the model of an atom proposed by Thomson?

191. What are the conclusions/observations made by Rutherford?

192. Explain the following terms.
(i) Proton,
(ii) Electron,
(iii) Neutron.

193. Explain the postulates of Dalton's atomic theory.

194. Write a brief account on pollination.

195. Explain the underground stems.

196. Write a note an sub aerial modifications of the stem.

197. Draw a diagram to show the life cycle of a plant.

198. Write about any three Communicable diseases in details.

199. List the situations in which first aid is given. What would you do if a person suffers from skin burns?

200. How the disease are transmitted from one person to the other person?

201. Write a note on causes and symptoms of Anaemia.

202. List the diseases affecting the eye, their causative agents, impact and Remedial measures.

203. With the help of Microsoft Photostory how will you create a video on a photostory?

204. Draw the diagram of a clinical thermometer and label its parts.

205. Go to a veterinary doctor (a doctor who treats animals). Discuss and find out the normal temperature of domestic animals and birds.

206. Explain the construction and working of a dry cell.

207. A student made a circuit by using an electric cell, a switch, a torch bulb (fitted in the bulb holder) and copper connecting wires. When he turned on the switch, the torch bulb did not glow at all. The student checked the circuit and found that all the wire connections were tight.
1)What could be the possible reason for the torch bulb not glowing even when the circuit appears to be complete?

208. Peeled and unpeeled banana does not look the same. Does that mean peeling banana is a chemical change?

209. A very hot glass on putting in cold water cracks. What does this change indicate?

210. Boiling of water is a physical change; but boiling of egg is a chemical change. Why?

211. Write about any three organelles in detail.

212. In a situation, how to explain, while your friend ask what is this, never seen before?

213. Give an account on the classification of invertebrates with few general features and examples.

214. Which kingdom has saprophytic, parasitic and symbiotic nutrition. Why?