Class-5 Hindi Chapter-19 अँधेरी रात के बाद

 EVENTS CONVENT HIGH SCHOOL

29/01/2021             CLASS-5                   SLOT-2

Chapter-19 HINDI
अँधेरी रात के बाद
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श्रुतिलेख

1.   रामपुर

2.   मशहूर

3.   तलवारें

4.   चांदी

5.   दम

6.   लोहार

7.   हंसिए

8.   निराश

9.   चुपचाप

10. थकावट

11. भाले

12. सुरक्षा

13. उपयोग

14. दृश्य

15. अँधेरी

 

1. प्रश्नो के उत्तर लिखे:-

प्रश्न 1. लालू कौन सा हथियार बनाता था?

उत्तर 1.लालू बछिया भाले और तलवारे बनाता था।

प्रश्न 2. तलवार के स्थान पर लालू क्या बनाने लगा

उत्तर 2. तलवार के स्थान पर लालू खेती में उपयोग होने वाले औजार बनाने लगा।

प्रश्न 3.लुटेरों के रोकने पर लालू ने क्या कहा?

उत्तर. लुटेरों के रोकने पर लालू ने कहा मैं लालू लोहार हूं मेरे पास कुछ नहीं विश्वास ना हो तो मेरी तलाशी ले लीजिए

प्रश्न 4.लालू कैसा कारीगर था?

उत्तर .लालू के अच्छा कारीगर था | उसका नाम आसपास के गावों में मशहूर था|

प्रश्न 5.लालू को अपने किए पर पछतावा कब हुआ?

उत्तर .जब लालू ने देखा कि उसकी बनाई तलवारे लोग लड़ाई झगड़े में उपयोग कर रहे हैं और लुटेरे उसकी तलवार को उपयोग करते हैं तो उसे पछतावा हुआ।

प्रश्न 6.लालू वेश बदलकर क्या देखने गया और क्यों?

उत्तर .लालू भेष बदलकर यह देखने गया कि लोग उसकी बनाई तलवार का उपयोग किस प्रकार करते हैं

 प्रश्न 7. हर अंधेरी रात के बाद एक नहीं सुबह आती है इस कथन का आशय क्या है?

उत्तर .छोटा हर अंधेरी रात के बाद एक नई सुबह आती है इस कथन का आशय यह है कि हर बुराई खत्म हो जाती है और अच्छाई की शुरुआत होती है।

 

Class-8 Science Chapter-12 Friction

 EVENTS CONVENT HIGH SCHOOL

29/01/2021             CLASS-8                   SLOT-2

Science Chapter-12 
friction
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Question 1.Fill in the blanks.

(a) Friction opposes the relative motion between the surfaces in contact with each other.

(b) Friction depends on the smoothness (or irregularities or nature) of surfaces.

(c) Friction produces heat

(d) The sprinkling of powder on the carrom board reduces friction.

(e) Sliding friction is less than the static friction.

 

Question 2.Four children were asked to arrange forces due to rolling, static and sliding frictions in decreasing order. Their arrangements are given below. Choose the correct arrangement.

(a) rolling, static, sliding

(b) rolling, sliding, static

(c) static, sliding, rolling

(d) sliding, static, rolling

Solution:

(c) static, sliding, rolling.

 Question 3.Alida runs her toy car on a dry marble floor, wet marble floor, newspaper and towel spread on the floor. The force of friction acting on the car on different surfaces in increasing order will be

(a) wet marble floor, dry marble floor, newspaper and towel.

(b) newspaper, towel, dry marble floor, wet marble floor.

(c) towel, newspaper, dry marble floor, wet marble floor.

(d) wet marble floor, dry marble floor, towel, newspaper.

Answer:

(a) wet marble floor, dry marble floor, newspaper and towel.

 Question 4.Suppose your writing desk is tilted a little. A book kept on it starts sliding down. Show the direction of frictional force acting on it.

Answer:Frictional force will act upward, i.e., the direction opposite to that of sliding book.

Question 5.You spill a bucket of soapy water on a marble floor accidentally. Would it make it easier or more difficult for you to walk on the floor? Why?

Answer:The layer of soap makes the floor smooth due to which the friction is reduced. This makes the floor slippery and the foot cannot make a proper grip on the floor. Therefore it is difficult to walk on a soapy floor. We may slip on the floor.

 

Question 6.Explain why sportsmen use shoes with spikes.

Answer:Sportsmen use shoes with spikes to increase the friction between shoes and the surface. So the shoes with spikes do not slip while the sportsmen run and play.

 

Question 7.Iqbal has to push a lighter box and Seema has to push a similar heavier box on the same floor. Who will have to apply a larger force and why?

Answer:A heavy object produces more friction as it is pressed hard against the opposite surface. So Seema will have to apply a larger force.

 

Question 8.Explain why sliding friction is less than static friction.

Answer:The sliding friction is less than static friction because the sliding object get less time to interlock into the contact points on the floor. So it is somewhat easier to move an object already in motion than to get it started.

 

Question 9.Give examples to show that friction is both a friend and a foe.

Answer:Some points are given below which show that friction is both a friend and a foe:

Friction as a friend:

It allows us to grip and catch any object.

It helps us to walk comfortably on the floor.

It helps to minimise the speed or to stop any moving object.

It helps us to write.

Friction as a foe:

It causes wear and tears in objects.

It causes damage to the parts of machines and tools which further require money to get them repaired.

It reduces the speed of moving objects, so more force is required.

It produces hurdles in moving any object freely.

Question 10.Explain why objects moving in fluids must have special shapes.

Answer:The objects moving in fluids must have a special shape to overcome the fluid friction acting on them. Efforts are therefore made to minimise the friction, so objects are given special shape having pointed fronts with little broader middle portion which gets tapered at the back called streamlined.

 

Class-7 Science Chapter-5 Acids, bases and salts

 EVENTS CONVENT HIGH SCHOOL

29/01/2021             CLASS-7                   SLOT-2

Chapter-5 Science
acids, bases and salts
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Q.1 State Difference between Acids and bases:-
Ans.

      

Q.2.Ammonia is found in many household products, such as window cleaners. It turns red litmus blue. What is its nature?

Ans.Ammonia has basic nature.

 Q.3.Name the source from which litmus solution is obtained. What is the use of this solution?

Ans.Litmus solution is extracted from lichens. It is used to determine whether the given solution is acidic or basic.

 Q.4.Is the distilled water acidic/basic/neutral? How would you verify it?

Ans.Distilled water will be neutral. We can verify it by showing that neither blue nor red litmus paper changes its colour when dipped in it.

Q.5.Describe the process of neutralisation with the help of an example.

Ans.The reaction between an acid and a base is known as neutralisation. Salt and water are produced in this process with the evolution of heat.

Antacids like milk of magnesia (magnesium hydroxide), baking soda, etc. which contain a base are used for reducing acidity in stomach when excessive acid released by glands.

 

Q.6.Mark ‘T’ if the statement is true and ‘F’ if it is false:

(i) Nitric acid turns red litmus blue. (False)

(ii) Sodium hydroxide turns blue litmus red. (False)

(iii) Sodium hydroxide and hydrochloric acid neutralise each other and form salt and water. (True)

(id) Indicator is a substance which shows different colours in acidic and basic solutions. . (True)

(v) Tooth decay is caused by the presence of a base. (False)

Q.7. Dorji has a few bottles of soft drink in his restaurant. But, unfortunately, these are

not labelled. He has to serve the drinks on the demand of customers. One customer wants acidic drink, another wants basic and third one wants neutral drink. How will Dorji decide which drink is to be served to whom?

Ans.Dorji can decide with the help of litmus paper:

(i) The drink which would turn a red litmus blue would be basic.

(ii) If the drink turns a blue litmus to red would be acidic.

(iii) The drink which would not affect both red and blue litmus would be neutral.

 
Q.8.Explain why:

(a) An antacid tablet is taken when you suffer from acidity.

(b) Calamine solution is applied on the skin when an ant bites.

(c) Factory waste is neutralised before disposing it into the water bodies.

Ans.(a) We take an antacid such as milk of magnesia to neutralises the excessive acid released in stomach.

(b) Ant injects an acidic liquid (Formic acid) into the skin on biting which causes inflammation, to the skin. The effect of the acid can be neutralised by rubbing. Calamine solution which contains zinc carbonate which is very weak base and causes no harm to the skin.

(c) The wastes of factories contain acids. If acids are disposed off in the water body, the acids will harm the organisms. So factory wastes are neutralised by adding basic substances.

Q.9. Three liquids are given to you. One is hydrochloric acid, another is sodium hydroxide and third is a sugar solution. How will you identify them? You have only turmeric indicator.

Ans.Name of the substances Effect on turmeric indicator

1. Hydrochloric acid Yellow to blue

2. Sodium hydroxide Yellow to red

3. Sugar solution No change

 

Q.10. Blue litmus paper is dipped in a solution. It remains blue. What is the nature of the solution? Explain.

Ans. (i) It can be identified on the basis of the following observations : Bases change the colour of litmus paper to blue. As the colour of blue litmus paper is not affected, the solution must be basic.

(ii) If the solution is neutral, even then colour of litmus will not change.

Class-6 Science Chapter-4 Sorting materals into group

 EVENTS CONVENT HIGH SCHOOL

29/01/2021             CLASS-6                   SLOT-2

Chapter-4 science
sorting materials into groups
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Q. 1. Name five objects which can be made from wood.

Ans.

(i) Table

(ii) Chair

(iii) Doors

(iv) Boat

(v) Bed

Q.2. Select those objects from the following which shine:

Glass bowl, plastic toy, steel spoon, cotton shirt

Ans. Glass bowl and steel spoon are shining objects.

Q.3. Match the objects given below with the materials from which they could be made. Remember, an object could be made from more than one material and a given material could be used for making many objects.

Q. 4. State whether the statements given below are ‘true’ or ‘false’.

(i) Stone is transparent, while glass is opaque.         False

(ii) A notebook has lustre while eraser does not       False

(iii) Chalk dissolves in water.                          False

(iv) A piece of wood floats on water.                 True

(v) Sugar does not dissolve in water.                  False

(vi) Oil mixes with water.                             False

(vii) Sand settles down in water.                      True

(viii) Vinegar dissolves in water.                       True

Q. 5. Given below are the names of some objects and materials:

 Water, basket ball, orange, sugar, globe, apple and earthen pitcher Group them as:

Ans. (a) (i) Round shaped: Basket ball, apple, orange, globe, earthen pitcher.

(ii) Other shapes: Water, sugar.

(b) (i) Eatables: Water, orange, sugar and apple.

(ii) Non-eatables: Basket ball, globe and earthen pitcher.

 

VERY SHORT ANSWER TYPE QUESTIONS

1. Why do we need to group materials? Give one reason.

Ans: We often group materials for our convenience. It helps to describe their properties.

 2. Suggest two bases on which we can group objects.

Ans:(i) Material used in making the object, e.g. wood or metal/plastic.

(ii) Material of the object is soft or hard, or substance is soluble or insoluble in water.

3. Is a substance which can be compressed soft or hard?

Ans: Soft.

4. Select a lustrous material out of the following substances:

Ans: Aluminium.

5. Which material is generally used for making pens?Wood, aluminium, plastic, cotton

Ans:Plastic or metal.

SHORT ANSWER TYPE QUESTIONS

1. Write any four properties of materials.

Ans:

(a) Appearance

(b) Hardness

(c) Solubility

(d) Float or sink in water

(e) Transparency

 

2. Why is a tumbler not made with a piece of cloth?

Ans: We use tumblers made of glass, plastic and metal to keep a liquid. These substances can hold a liquid.

A tumbler made of cloth cannot hold a liquid because:

(i) Cloth piece is not hard enough to hold liquids and

(ii) Cloth piece has very minute pores through which the’liquid oozes out.

 

3. What are the similarities between iron, copper and aluminium?

Ans:(a) They all have lustre,

(b) They are all metals,

(c) They are hard.

4. Mention some materials which are made up of paper.

Ans: Books, notebooks, newspapers, toys, calendars, etc.

5. Why is water important for our body?

Ans: Water can dissolve a large number of substances, so it is needed by the body. It is also major part of our body cells.

LONG ANSWER TYPE QUESTIONS

1. ‘Grouping of objects helps the shopkeeper.’ Justify the statement.

Ans: Proper grouping of objects helps shopkeeper in the following ways:

(i) He can locate the required object easily and quickly.

(ii) He can easily come to know what stocks are going to finish and he should purchase them for his customers.

 

2. Describe an experiment to prove that water is transparent.

Ans: Take a beaker half-filled with clean water. Put a coin in beaker of water.

Place the beaker undisturbed for a few minutes where enough light is present. Now, observe the coin immersed in water from the top of the beaker. Are you able to see the coin? You can clearly see the coin immersed in water. This proves that water is a transparent liquid.

Draw

3. Write an experiment to show that our palm is translucent.

Ans: Cover the glass of a torch with your palm at a dark place. Switch on the torch and observe from the other side of palm. We see that the light of torch passes through palm but not clearly. This experiment shows that our palm becomes translucent when a strong beam of light passes through it.

Draw