The City School PAF Chapter

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1 The City School PAF Chapter Comprehensive Worksheet Answer Key May 2015 SCIENCE Class 6 The City School / PAF Chapter/ Comprehensive Worksheet/ May 2015 / Science / Class 6 / Ans Key Page 1 of 8

2 SECTION A Q.1 Fill in the blanks: [ /10] a. Fertilizers contain nutrients which plants need in small amounts to grow well. b. Animals help to disperse seeds. c. Clay soil cracks when it is dry. d. Fish have gills to allow them to breathe underwater. e. The first battery was made by Alassandro Volta. f. Adding more components in a series circuit will make it dimmer. g. It is safer to use batteries than mains electricity. h. When light hits a mirror it bounces off it. i. The flow of electrons in a circuit is called current. j. A black material that rises in smoke is called soot. producer _ Q2.Rewrite the underlined words to make the following statements correct. [ /10] a. Water and nutrients get into the plant through its stems. roots b.light cannot pass through translucent materials. opaque c. Carrots have prop roots. tap d.when water is added to quicklime it forms limestone. slacked lime e. Light always changes direction when it forms a shadow. an image f. Dull materials are good at reflecting light. shiny g.burning is a physical change. chemical h.when water is added to cement, it produces bubbles. heat i. Plastics are good electrical conductors. insulators j. Every food chain starts with a herbivore. The City School / PAF Chapter/ Comprehensive Worksheet/ May 2015 / Science / Class 6 / Ans Key Page 2 of 8

3 Q3. Match the following: [ /10] Column A Column B Column C 1. Two or more electrical cell joined Battery Dimmer together 2. Being on fire due to a reaction with Burning / Symbols oxygen Combustion 3. A change of shape or state Chemical change Physical change Reflective Conductors 4. Allows electricity to flow through material 5. Travel in straight lines Variable resistor Light rays 6. Used to represent components of a Symbols Battery circuit 7. A kind of change by mixing chemicals Conductor Chemical change 8. A kind of switch that turns up or down Physical change Dimmer 9. Shine when light falls on them Burning 10. Used to change the resistance of a circuit Light rays Reflective material Variable resistors Q4. Which of the following changes are reversible or irreversible, write in front of the statement. [ /10] i. Baking a cake I ii. Making cheese omelet I iii. Freezing an ice lolly R iv. Rusting of a nail I v. Frying an egg I vi. Chocolate melting R vii. Firing a pot I viii. Boiling water R ix. Puddle evaporating R x. Toasting bread I Q5.a) Identify the types of mirrors. [ /3] i. Flat surface, same sized image plane ii. Curved inwards, shows bigger image concave iii. Curved outwards, shows smaller image convex The City School / PAF Chapter/ Comprehensive Worksheet/ May 2015 / Science / Class 6 / Ans Key Page 3 of 8

4 Q5.b) Which mirrors do the following people/objects use: [ /5] i. Dentist concave ii. Barber plane iii. In the bathroom plane iv. Car driver convex v. In a magnifying glass concave Q5.c) Complete the following statements. [ /2] i. An image is formed when light rays are reflected By smooth shiny surface. ii. A shadow is formed when light rays are blocked by opaque objects. `Q6.a) Spot the mistakes. [ /10] Direction of arrows Light ray Because light from the candle is entering the girls eyes, so the direction should be towards the eye. Because wood is an opaque object and does not let light pass through. The City School / PAF Chapter/ Comprehensive Worksheet/ May 2015 / Science / Class 6 / Ans Key Page 4 of 8

5 6.b) Draw the shadows of the stick at different times of the day. The City School / PAF Chapter/ Comprehensive Worksheet/ May 2015 / Science / Class 6 / Ans Key Page 5 of 8

6 SUBJECTIVE Q1. Give scientific reasons. [ /10] i. Opaque objects form the darkest shadow they block light rays_ ii.wires are usually made of copper _they are best electrical conductors iii.glass mirrors reflect light better than metal ones _they have polished metal backing_ iv.builders and workers wear reflective jackets _so that they can be seen by drivers at night v.we should not touch the bare metal parts of plugs _Metals are conductors they can give a bad shock vi.we can see things through a glass window _they let light to pass through vii.a solar eclipse can be seen from some parts of the Earth _moon is smaller than the sun and earth viii.an earth worm has a pointed head for living in the soil _so that it can easily burrow and move in the soil_ ix.we are able to see objects _beacuse light rays are reflected and enter our eyes x.moon is a non-luminous object but shines at night _It reflects the sunlight_ The City School / PAF Chapter/ Comprehensive Worksheet/ May 2015 / Science / Class 6 / Ans Key Page 6 of 8

7 Q2. Look at the food web given below and answer the following questions. [ /10] a. Identify and write any one food chain from the given web. [ /2] _multiple answers_ b. List any 4 primary consumers. [ /2] _multiple answers_ c. Name two animals which are both prey and predator. [ /2] snake and lizard_ d. Identify two secondary consumers. [ /2] _multiple answers_ e. What would happen to the food web if all the producers die? [ /2] _nothing will survive Q3.a) Imagine you have made a simple circuit using a battery, a switch, wires and a bulb. The bulb does not light up. What might be wrong? Think of four ways and describe them. [ /04] multiple answers The City School / PAF Chapter/ Comprehensive Worksheet/ May 2015 / Science / Class 6 / Ans Key Page 7 of 8

8 Q3.b) How could you make a bulb in a circuit shine with a dimmer light? Think of two ways and describe them. [ /2] multiple answers_ Q3.c) Your friend wants to make a circuit for a room but he is puzzled to use a series or a parallel circuit. Can you guide him by telling him at least two properties of each circuit? [ /4] multiple answers_ Q4. Some of your friends have a camp fire. They have collected wood to light a fire. At the end of the night there was only a pile of ashes left. [ /10] a. What has happened to the wood? [ /1] _wood has burnt and turned into ashes b. Is this a reversible change? Give reason to support your answer. [ /2] _no it is an irreversible change because new materials are made_ c. Explain why a candle will not burn without a wick? [ /2] _because a candle was provides fuel for burning but it does not burn. A wick is required to burn a candle d. Is melting of wax reversible or irreversible? Explain your answer. [ /1] it is reversible as it can be solidified again e. Write down at least two fire safety rules. [ /4] multiple answers The City School / PAF Chapter/ Comprehensive Worksheet/ May 2015 / Science / Class 6 / Ans Key Page 8 of 8