TIBETAN CHILDREN’S VILLAGE SCHOOLS CLASS VIII COMMON SA1 EXAMINATION – 2012 SCIENCE PAPER Time: 3:00 Hrs M.M: 90 General Instructions: 1. This question paper consists of two sections A (MCQ), and B ( Theory ) 2. Questions in section A are multiple choice questions carrying 1 mark each. You have to select one of the most appropriate response out of the four provided to you. 3. Question numbers 1 to 5 carries 1 mark each. These are to be answered in one word or one sentence. 4. Question numbers 6 to 15 carries 2 marks each. These are to be answered normally in about 30 words each. 5. Question numbers 16 to 25 carries 3 marks each. Their answers may not normally exceed 60 words. 6. Question numbers 26 to 28 are long answer type questions carrying 5 marks each. These are to be answered in about 70 words each.
SECTION A (MCQ) Q1. A student has performed an activity in which he has taken 4 beakers A, B, C, and D containing Copper Sulphate solution (CuSO4). Then he dissolved in each beaker a teaspoonful of substances as follows: 1. CuSO4 + Zn→ 2. CuSO4 + Fe→ 3. CuSO4 + Cu→ 4. CuSO4 + Ag→ In which solution will he get displacement reaction? I) Beaker B II) Beaker C III) Beaker A and B IV) Beaker D Q2. Tenzin has collected a spoonful of rust and dissolved it in a very little amount of water. He find that the rust remain suspended in water. After shaking well he test the solution with red and blue litmus paper. What did he observe? I) Red litmus paper turning into blue II) Blue litmus paper turning into red III) Both I and II IV) None of the above Q3. Which solution from the following will glow the bulb in the given circuit?
I) Sugar solution II) Distilled water
III) Alcohol IV) Lemon Juice
Q4. When an electric current is passed through the CuSO 4 Solution, it dissociated into Cu and SO4. In this process of electroplating, the free Cu get drawn to which terminal of the battery. I) Positive terminal II) Negative terminal III) Both the terminal IV) None of the above Q5. Tin cans are used for storing food because: I) They are cheap II) They are reactive metal
III) They help in keeping the food hot IV) They protect the food for longer period.
Q6. In LED, one Lead is slightly longer than the other. The lead which is always connected to the positive terminal of the battery is: I) Longer lead II) Shorter lead III) Both the lead are of same size IV) None of the above Q7. Which process of reproduction is shown by this diagram?
I) Budding III) Metamorphosis
II) Embedding IV) Fertilisation
Q8. External fertilization occurs in: I) Mammal III) Fishes
II) Birds IV) Reptile
1
Q9. Observe the given life cycle of frog carefully and name the stage marked in diagram:
I) Adult Frog III) Late tadpole
II) Eggs IV) Early Tadpole
Q10. The number of nuclei present in a zygote is: I) Two II) One
III) Four IV) None
Q11. Reproductive age in women starts when their: I) Menstruation starts II) Breast starts developing
III) Body weight increases IV) Height increases
Q12. Menarche in the reproductive life of a women refer to I) The first menstrual flow II) The last menstrual flow
III) Irregularity in the menstrual flow IV) Periods of menstrual flow
Q13. The endocrine gland that is located on the kidney is called: I) Pancreas III) Adrenal gland
II) Thyroid Gland IV) Liver
Q14. Beautiful patterns are formed in a kaleidoscope because of: I) Single reflection III) Multiple reflection
II) Double reflection IV) Irregular reflection
Q15. Identify the protruding part given in the diagram:
I) Neck
II) Throat
IV) Adam’s apple
III) Oesophagus
Q16. Sunlight consists of: I) 3 Colours III) 4 Colours
II) 7 Colours IV) None of these
Q17. Image formed by a plane mirror is: I) Virtual, behind the mirror and enlarged II) Virtual, behind the mirror and of the same size as the object III) Real, at the surface of the mirror and enlarged IV) Real, behind the mirror and of the same size as the object Q18. The image of an object is formed at the: I) Iris II) Pupil
III) Lens IV) Retina
Q19. Which one is correct among the following? I) A sound pleasing to ear is music II) An undesirable sound is noise
III) A sound which can be heard is audible IV) All of these
Q20. Voice of which of the following is likely to have minimum frequency? I) Baby girl III) A man II) Baby boy IV) A Woman
2
SECTION B Q1. Name the non – metal which we inhale during breathing. 1 Q2. If electrodes were immersed in water and a current was passed, the bubbles of gases were produced. Name these gases. 1 Q3. Name the stage of embryo development in which all the body parts can be identified. 1 Q4. Tenzin’s mother gave birth to another child with two X chromosome. Can you tell what the sex of baby is? 1 Q5. What is the angle of incidence of a ray, if the angle of reflection is 0 0 by a plane mirror? 1 Q6. An element X combines with oxygen to form an oxide X 2O. When X2O is added to water it turnsred litmus blue. a) Is “X” a metal or a non – metal? 1 b) Is X oxide an acid or base? 1 Q7. Give a balanced chemical equation when sulphur dioxide is dissolved in water. What is the nature of the product formed? 2 Q8. Water from taps and hand pumps conducts electricity but distilled water does not. Why? How can you make distilled water conduct electricity? 2 Q9. Write the full form of LED. Why we use an LED in place of the electric bulb in the tester? 2 Q10. Classify the following animals as viviparous and Oviparous: Cat, Hens, Snake and an elephant 2 Q11. Do you think human beings undergo metamorphosis? Support your answer. 2 Q12. a) What is the most important change which marks puberty in boys and girls? 1 b) When does the puberty end? 1 Q13. A 60 cm long boy is looking at his image in the plane mirror. a) What is the size of his image? 1 b) What is the nature of his image? 1 Q14. Draw a diagram showing regular and irregular reflection. 2 Q15. Define the following term: a) Frequency 1 b) If an object oscillates 40 times in two second. What would be its frequency? 1 Q16. Give reason: a) Sodium is always kept in kerosene 1 b) Aluminium is used as foil 1 c) Gold is used as jewels 1 Q17. How do metals differ from non-metals in terms of? a) Physical state 1 b) Conductivity 1 c) Ductility 1 Q18. Write true or false against the following statement: a) During electrolysis of water, hydrogen gas is collected at the positive electrode. 1 b) During electroplating the object to be plated is connected to the negative terminal of the battery 1 c) Copper can be refined by electrolysis 1 Q19. Label any three part of male reproductive organ in the following diagram. 3
Q20. Give reason: a) What purpose does the tail in the sperm serve? 1 b) Why do fishes and frogs lay eggs in hundred whereas a hen lay only one egg at a time? 1 c) How could a single cell become such a big individual? 1 Q21. List three secondary sexual character of a female which they observe during adolescence. 3 Q22. Answer the following questions: a) A set of two plane mirrors were placed at 90º to each other. A ray of light falls on one mirror at an angle of 60º as shown in figure below. Draw the reflected ray from the second mirror with proper labeling. 1 b) How many images of a candle will be formed if it is place between two parallel plane mirrors separated by 10 cm. 1 c) How do visually challenged persons read and write?
3
1
Q23. Give reasons: a) Why is a woman’s voice more shrilling than a man’s voice? b) Name the factors that affect the “pitch” and “loudness” of a sound. c) In which medium does the sound travel fastest?
1 1 1
Q24. Give three points on how noise pollution is harmful to human. Q25. The bulb does not glow in the set up shown in figure. List three possible reasons.
3 3
Q26. I) Pair up the term given in column A with those in column B 3 COLUMN “A” COLUMN “B” a) Sulphur dioxide luster b) Copper water purification c) Chlorine Electric wire d) Hydrogen gas Turns blue litmus red e) Iodine fuel f) Carbon Pop sound I) Tashi took a piece of burning charcoal and collected the gas evolved in a test tube. How will he find the nature of the gas? 2 Q27. Complete the following table: 5
Gland
Hormone secreted
Action of hormone
1. Thyroid
…………………………………
Regulate growth and metabolism
2. ……………….
………………………………..
3. ………………. 4. ……………….
Insulin Growth hormone
Controls heart beat and blood pressure. Regulate Regulates the amount of sugar in blood. Controls growth in human body
Q28. i) Label any six part of human eye given below:
3
ii) Suggest two ways to take care of our eye.
2
BEST OF LUCK
4