Sunday, May 1, 2022

HOLIDAYS HOMEWORK, CLASS 6, 2022-23

 1. Given below are names of some animals.

(i) Goat

(ii) Human beings
(iii) Cockroach

(iv) Eagle
which of the above animals form a pair of omnivores?
(a) (i) and (ii)
(b) (ii) and (iii)
(c) (iii) and (iv)
(d) (ii) and (iv)


2. Below are the names of some animals.
(i) Cow
(ii) Sheep
(iii) Horse
(iv) Ox
Which of the above are sources of milk for human beings?
(a) (i) and (iii)

(b) (i) and (ii)
(c) (ii) and (iii)

(d) (iii) and (iv)


3. Name two ingredients in our food that are not obtained from plants or animals. Mention one source for each ingredient.

4. Why do organisms need food? Write two reasons.

5. Label and colour the different parts of the plant given below in Fig. 1.2.



6. Connect the animal with the food it eats by an arrow using different colours in Fig. 1.4. One is done for you.

7. Read the items of food listed below. Classify them into carbohydrate-rich, protein-rich and fat-rich foods and fill them in the given table. Moong dal, fish, mustard oil, sweet potato, milk, rice, egg, beans, butter, buttermilk (chhachh), cottage cheese (paneer), peas, maize, white bread.

Carbohydrate Rich food Item (A)Protein Rich food Item (B)Fat Rich food Item (C)
………….…….
………….…….
………….…….

8. While using iodine in the laboratory, some drops of iodine fell on Paheli’s socks and some fell on her teacher saree. The drops of iodine on the saree turned blue-black while their colour did not change on the socks. What can be the possible reason?

9. Solve the crossword puzzle given as fig. 2.1 from the clues (in blue colour)  given below.

Across
1. Lack of nutrients in our diet over a long period causes these diseases (10)
2. Rice and potato are rich in this type of carbohydrate (6)
3. Deficiency disease in bones making it become soft and bent (7)
4. The diet that provides all the nutrients that our body needs, in right quantities, along with an adequate amount of roughage and water (8, 4)
5. Deficiency disease with bleeding gums (6)
6. Disease caused due to deficiency of iodine (6)
Down
7. Starch and sugar in our food are rich in this type of energy-giving nutrient (13)
8. The term is given to the useful components of food (9)
9. The disease caused by a deficiency of iron in diet (7)
10. Green leafy vegetables, liver and apples are rich in this mineral (4)
11. Deficiency disease caused due to lack of vitamin B in the diet (8)


10. The correct sequence to get cloth is
(a) fibre → fabric → yarn
(b) fibre → yarn → fabric
(c) fabric → yarn → fibre
(d) yarn → fibre → fabric.


11. 
 Fill in the blanks to complete the life story of cotton fibre.
My parents, cotton plants were grown in_______soil and ______climate. The plants bore fruits called______. I, the cotton fibre was separated from seeds in the cotton bolls by the process of _______. Other cotton fibres and myself were made into yarn by the process of _____. The yarn was ______to give beautiful colours and then to get cotton fabric.

12. Match the terms given in column I with the statements given in column II.

Column IColumn II
(a) Weaving(i) A single yarn used to make a fabric
(b) Knitting(ii) Combing of cotton fibres to remove seeds
(c) Spinning(iii) Yarns are made from these thin strands
(d) Ginning(iv) These are spun from fibres and then used to make fabrics
(e) Fibre(v) Process of arranging two sets of yarns together to make a fabric
(f) Yarn(vi) Process of making yarn from fibres


Tuesday, February 8, 2022

CLASS TEST, CLASS 6,Water CHAPTER 14

 MULTIPLE CHOICE QUESTIONS  (1 marks each)

1. Which of the following activity does not involve use of water? 

(a) Washing clothes (b) Bathing (c) Cleaning utensils (d) Drying wet clothes 

2. In which of the following activities will you use minimum amount of water? 

(a) Bathing (b) Brushing teeth (c) Washing clothes (d) Mopping a room 

3. The quantity of water required to produce one page of your book is

 (a) one bucket (b) ten buckets (c) two glasses (d) few drops

4. Water in our tap comes from a 

(a) river (b) lake (c) well (d) river, lake or well 14 Water 

 5. In which of the following case evaporation of water will be slowest? 

(a) A tray of water kept in sunlight. (b) A kettle of water kept on a burner. (c) A glass of water kept in a room. (d) A bucket of water kept on rooftop. 

6. Transpiration is a process in which plants 

(a) receive water from soil. (b) absorb water vapour from air. (c) prepare food from water. (d) release water vapour.

 7. Clouds are 

(a) tiny drops of water floating in air. (b) mixture of dust and water vapour. (c) particles of water vapour. (d) rain drops in air. 

8. Wells are fed by

(a) pond water. (b) lake water. (c) rain water. (d) ground water.

 9. Floods cause extensive damage to 

(a) crops. (b) property and human life. (c) domestic animals. (d) all of the above.  

10. “Catch water where it falls” is the basic idea behind 

(a) recycling of water. (b) making dams to store water. (c) rain water harvesting. (d) condensation of water vapour.

SHORT ANSWER QUESTIONS

11. Why do wet clothes placed on a clothes line get dry after some time? Explain.  (2)

12. Water kept in sunlight gets heat from sun and is evaporated. But how does water kept under the shade of a tree also gets evaporated? Explain.   (2)

13. How do the areas covered with concrete affect the availability of ground water?(3)

14. 18. Fill in the blanks selecting words from the following list snow, rain, clouds, vapour, evaporation, transpiration. Water, as _____ goes into atmosphere by the processes of ______ and _____ and forms ________, which on condensation fall in the form of ______ and _______.   (3)

Monday, February 7, 2022

CLASS TEST, Pollution of Air and Water, CLASS 8

MULTIPLE CHOICE QUESTIONS (1 MARK EACH) 

1. Air is a mixture of various gases. One of the gases is 21% part of the air and is essential for the survival of human beings. This gas is 

(a) nitrogen (c) ozone (b) oxygen (d) argon 

2. Which of the following is not a source of air pollution? 

(a) automobile exhaust (c) windmill (b) burning of firewood (d) power plant 

3. Boojho wishes to contribute in reducing air pollution. Which vehicle should he use for going to school? 

(a) car (c) autorickshaw (b) school bus (d) scooter

4. Which of the following is not a way to conserve water? 

(a) replace (c) reuse (b) reduce (d) recycle 

5. The type of pollution which is likely to affect Taj Mahal in Agra to a greater extent is

 (a) air pollution (c) soil pollution (b) water pollution (d) noise pollution 

6. Incomplete combustion of fuel such as petrol and diesel gives

 (a) nitrogen oxide (c) carbon monoxide (b) sulphur dioxide (d) carbon dioxide 

7. The phenomenon of marble cancer is due to 

(a) soot particles (c) fog (b) CFCs (d) acid rain

 8. Potable water is the water which is

(a) obtained from a river. (c) pure and fit for drinking. (b) obtained from a lake. (d) used only for washing clothes. 

9. Which of the following procedures will give you water free from all impurities? 

(a) adding chlorine tablets (c) boiling (b) distillation (d) filtration 

10. A pond contains clean water. Which of the following activities will produce least pollution of water? 

(a) washing clothes in the pond (b) animals bathing in the pond (c) washing motor vehicles in the pond (d) swimming in the pond. 

11. Trees help in reducing the pollution of our environment. Lakhs of trees are planted by people in the month of July every year. The occasion is called

 (a) forest Conservation Day (c) Van Mahotsav (b) plantation month (d) wildlife week 

12. Which of the following is not a green house gas? 

(a) nitrogen gas (c) methane gas (b) water vapour (d) carbon dioxide 

VERY SHORT ANSWER QUESTIONS (2 MARKS EACH)

13. Name the chemicals which are used in refrigerators and air conditioners and damage ozone layer when released in air. 

14. Name any two sources which cause air pollution due to suspended particulate matter. 

15. Name two gases which are mainly responsible for acid rain? 

16. The quality of air at various locations is monitored regularly by government and other agencies? In what way can you use these data? 

17. Combustion of fossil fuels generates a lot of air pollution. Can you suggest any two alternative sources of energy which do not cause any pollution? 

18. Name any two water pollutants which are toxic for plants and animals



Sunday, February 6, 2022

Class test, Class 6, AIR AROUND US

Q1.  Fill in the Blanks:      (5)

1. The layer of air around the earth is known as ………………….. .
2. The component of air used by green plants to make their food, is ………………… .
3. Air is a gaseous …………….. .
4. …………….. is used to inflate tyres of vehicles.
5. The ………………… present in air helps in the formation of clouds.

Q2.Tick (✓) the Correct Option:      (6)

1. Air is a/an:
(a) mixture
(b) compound
(c) element
(d) none of these

2. Which is the largest component of air?
(a) Oxygen
(b) Nitrogen
(c) Carbon dioxide
(d) Water vapour

3. Air occupies space and has:
(a) colour
(b) smell
(c) mass
(d) none of these

4. ……………….. is a device which measures the air pressure.
(a) Barometer
(b) Thermometer
(c) Anemometer
(d) Ammeter

5. Which gas is released in respiration

(a) Nitric acid

(b) Carbon monooxide

(c) Carbon dioxide
(d) Sulphur dioxide

6. To release some of the air from the bottle shown in the given diagram, we should:
CBSE Class 6 Science Air Around Us Worksheets 1

(a) push the glass further down

(b) tilt the glass
(c) pour more water into the basin
(d) blow bubbles into the glass

Q3. State True or False:        (5)

1. Air has no mass. ………………….
2. Air is a mixture of gases. ……………….
3. Air exerts pressure. ……………….
4. Nitrogen supports burning. ………………
5. Sound can travel only in air. …………….

Q4. Match the following:      (4)

‘A’‘B’
1. Breezea. Moving air
2. Stormb. Slow moving air
3. Smokec. Air with very high speed
4. Windd. Air with ash particles

Q5. Arrange the jumbled words given below in proper form:  (4)

1. DILLMWIN ………………..
2. YNOGXE ……………….
3. TUDS ………………..
4. MESKO ………………

Q6. What is the composition of air?            (2)
Q7. Which gas in the atmosphere is essential for respiration?       (2)
Q8. Why the transparent glass of windows, if not wiped off regularly, appears hazy?  (2)

Thursday, February 3, 2022

Stars And The Solar System, Class 8 Science Chapter 17, CLASS TEST

 1. Morning star is the name given to    (1)

(a) pole star

(b) star Sirius

(c) planet Jupiter

(d) planet Venus


2. Which of the following figures depicts the position of pole star correctly?   (1)

NCERT Exemplar Class 8 Science chapter 17 Solutions fig 1


3. Sun appears to move from east to west around the earth. This means that earth rotates from  (1)

(a) east to west

(b) west to east

(c) north to south

(d) west to north


4. An astronaut standing on the surface of the moon throws a ball upwards. The ball would  (1)

(a) directly fall down from the point it is released.

(b) hang in space.

(c) go up and then come back to the surface of the moon.

(d) keep going up never to come back.


5. Suppose a new planet is discovered between Uranus and Neptune. Its time period would be  (1)

(a) less than that of Neptune.

(b) more than that of Neptune.

(c) equal to that of Neptune or Uranus.

(d) less than that of Uranus.


6. The change in seasons on the earth occurs because   (1)

(a) the distance between the earth and the sun is not constant.

(b) the axis of rotation of the earth is parallel to the plane of its orbit.

(c) the axis of rotation of the earth is perpendicular to the plane of its orbit.

(d) the axis of rotation of the earth is tilted with respect to the plane of its orbit.


7. The first of a month is the new moon day. On fifteenth of the same month, which of the following figures would represent the phase of the moon?   (1)

NCERT Exemplar Class 8 Science chapter 17 Solutions fig 2


8. Do stars emit light only during night?   (1)


9. Paheli and Boojho observe a bright object in the night sky which was not twinkling. Paheli says, it is a star and Boojho says it is a planet. Who is correct?  (1)


10. State whether the following statements are ‘True’ or ‘False’.  (3)

(a) The planet nearest to us is Jupiter.

(b) All the stars are at the same distance from us.

(c) The planets do not emit light of their own.

(d) The planets keep changing their position with respect to stars.

(e) The planet Venus appears in the eastern sky before sunrise.

(f) The plane in which the earth revolves around the sun is called the equatorial plane of earth.


11. Explain with a diagram of how you can locate pole star with the help of the constellation Great Bear (Ursa Major).  (3)

Wednesday, February 2, 2022

Garbage In, Garbage Out, Ch 16, class 6

 1. The method of preparing compost with the help of earthworms is called   (1)

(a) composting
(b) vermicomposting
(c) manuring
(d) decomposing

2. If you dump kitchen waste in a pit, it may, after sometime    (1)
(a) convert into compost
(b) convert into vermicompost
(c) remain as such
(d) remain forever in its dried form.

3. Which of the following activities does not reflect responsible behaviour with regard to waste disposal?   (1)
(a) Goods carried m paper bags or cloth bags.
(b) Waste collected in polythene bags for disposal.
(c) Waste separated into those that degrade and those that do not.
(d) Making handicrafts with used up notebooks.

4. Paheli gave the following ill effects of the practice of burning dried leaves and other plant parts.
(i) Burning degrades the soil.   (1)
(ii) Burning produces harmful gases/fumes.
(iii) Precious raw materials to obtain manure at a low cost is lost.
(iv) Lot of heat is generated unnecessarily.
The correct reasons of why we should not burn leaves are
(a) i, ii and iv only
(b) i, ii, iii and iv
(c) ii and iii only
(d) ii, iii and iv only.

5. A garbage collector separate items mentioned below in the garbage into red, green and blue containers for their transfer to landfill, composting pit, and recycling unit respectively.
Items:     (2)
(i) Plastic bags
(ii) Newspaper and journals
(iii) Screw and nuts
(iv) Vegetable peels
(v) Metal chips
(vi) Eggshells
Which item was transferred to which bin?
REDGREENBLUE
(a)(i) and (iv)(ii) and (iii)(v) and (vi)
(b)(i) and (iii)(ii) and (v)(iv) and (vi)
(c)(i), (iii) and (v)(iv) and (vi)(ii) only
(d)(i) and (v)(ii) and (iv)(iii) only
6. The steps required for conversion of kitchen garbage into manure are given below in a jumbled form.                                                   (1)
(i) Put garbage in a pit.
(ii) Cover the bottom of the pit with sand.
(iii) Cover the pit loosely with a gunny bag or grass.
(iv) Add worms.                
Which of the following shows the correct sequence of the above steps?
(a) (ii); (i); (iii); (iv)
(b) (i); (ii); (iii); (iv)
(c) (ii); (iv); (i); (iii)
(d) (iv); (i); (ii); (iii)

7. Read the items mentioned in columns-l and II and fill in the related process in column III.  (3)

Column IColumn IIColumn III
(a) Organic wasteEarthworms(i) ……………
(b) GarbageDig pit and fill with garbage(ii) ……………
(c) Old newspaperPaper bags(iii) ……………
8. Correct the definitions of certain terms given below by changing only one word.      (3)
(i) Compost: Substances converted into manure for use in industries.
(ii) Landfill: Garbage buried underwater in an area.
(iii) Recycling: Reuse of unused material in the same or another form.

9. Provide a suitable term that expresses the meaning of each of the following statements.     (2)
(a) Greeting cards made from newspaper.
(b) Contents of the waste bins.
(c) Worms converting certain kinds of waste into manure.
(d) An area where a lot of garbage is collected, spread out and covered with soil.

10.Put a tick (✓) against the garbage items given in Table 16.1 which could be converted into manure. Put a cross (X) against the others.                                (5)
Garbage ItemsMake manure or not
(i)Eggshells
(ii)Straw
(iii)Dry flowers
(iv)Pebbles
(v)Broken pieces of glass
(vi)Nails and screws
(vii)Plastic bangles
(viii)Leftover food
(ix)Steel broken vessel
(x)Dead animals

Friday, January 14, 2022

Friction (CH 12) and Sound (CH 13), CLASS 8

 1. A list of mediums is given below.

(i) wood

(ii) water

(iii) air

(iv) vacuum

In which of these mediums can sound travel?

(a) i & ii only

(b) i, ii & iii only

(c) iii & iv only

(d) ii, iii & iv only


2. The loudness of a sound depends on:

(a) its amplitude.

(b) its frequency.

(c) its time period.

(d) its speed.


3. Which of the following statements are correct?

(i) Sound is produced by vibrations.

(ii) Sound requires a medium for propagation.

(iii) Light and sound both require a medium for propagation.

(iv) Sound travels slower than light.

(a) i & ii only

(b) i, ii & iii only

(c) ii, iii & iv only

(d) i, ii & iv only


4. An object is vibrating at 50 hertz. What is its time period?

(a) 0.02 s

(b) 2 s

(c) 0.2 s

(d) 20.0 s


5. In order to reduce the loudness of a sound, we have to

(a) decrease its frequency of vibration of the sound.

(b) increase its frequency of vibration of the sound.

(c) decrease its amplitude of vibration of the sound.

(d) increase its amplitude of vibration of the sound.


6. The loudness of sound is determined by the

(a) amplitude of vibration

(b) the ratio of amplitude and frequency of vibration

(c) frequency of vibration

(d) product of amplitude and frequency of vibration


7. 1 hertz is equal to

(a) 1 vibration per minute

(b) 10 vibrations per minute

(c) 60 vibrations per minute

(d) 600 vibrations per minute


8. Pitch of sound is determined by its

(a) frequency

(b) amplitude

(c) speed

(d) loudness


9. Ultrasound has a frequency of vibration

(a) between 20 and 20,000 Hz

(b) below 20 Hz

(c) above 20,000 Hz

(d) between 500 and 10,000 Hz


10. 
Whenever the surfaces in contact tend to move or move with respect to each other, the force of friction comes into play

(a) only if the objects are solid.

(b) only if one of the two objects is liquid.

(c) only if one of the two objects is gaseous.

(d) irrespective of whether the objects are solid, liquid or gaseous.


11.  To sharpen the blade of a knife by rubbing it against a surface, which of the following will be most suitable?

(a) stone

(b) plastic block

(c) wooden block

(d) glass block


12. If we apply oil on door hinges, the friction will

(a) increases

(b) decreases

(c) disappear altogether

(d) will remain unchanged


13. Which of the following statements is incorrect?

(a) Friction acts on a ball rolling along the ground.

(b) Friction acts on a boat moving on water.

(c) Friction acts on a bicycle moving on a smooth road.

(d) Friction does not act on a ball moving through air.


14. A boy rolls a rubber ball on a wooden surface. The ball travels a short distance before coming to rest. To make the same ball travel longer distance before coming to rest, he may

(a) spread a carpet on the wooden surface.

(b) cover the ball with a piece of cloth.

(c) sprinkle talcum powder on the wooden surface.

(d) sprinkle sand on the wooden surface


15. In a large commercial complex, there are four ways to reach the main road. One of the paths has loose soil, the second is laid with polished marble, the third is laid with bricks and the fourth has a gravel surface. It is raining heavily and Paheli wishes to reach the main road. The path on which she is least likely to slip is

(a) loose soil.

(b) polished marble.

(c) bricks.

(d) gravel.


16. Two boys are riding their bicycles on the same concrete road. One has new tyres on his bicycle while the other has tyres that are old and used. Which of them is more likely to skid while moving through a patch of the road which has lubricating oil spilt over it?


17.  Imagine that an object is falling through a long straight glass tube held vertical; the air has been removed completely from the tube. The object does not touch the walls of the tube. Will the object experience any force of friction?


18. Lightning can be seen as the moment it occurs. Paheli observes lightning in her area. She hears the sound 5 s after she observed lightning. How far is she from the place where lightning occurs? (speed of sound = 330 m/s).


19. Boojho saw a cracker burst at night at a distance from his house. He heard the sound of the cracker a little later after seeing the cracker burst. Give the reason for the delay in hearing the sound.


20. A simple pendulum makes 10 oscillations in 20 seconds. What is the time period and frequency of its oscillation?