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Difference between scavenger bag and suicidal bag

Posted by Ayush Singh 7 years, 5 months ago

CBSE > Class 09 > Science

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ANSWER

Calculate the number of aluminium ions present in 0.051 g of aluminium oxide

Posted by Bhanu Pratap Singh 7 years, 5 months ago

CBSE > Class 09 > Science

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Fxplain the principle of antibiotics action

Posted by Deepak Virat 7 years, 5 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

Why are lysosomes called suicide bags

Posted by Adharsh S Nair 7 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Soyab Idrishi 7 years, 5 months ago

lysosomes are known as suicidal bag of cell because during the disturbance in cellular metabolism when the cell gets damaged lysosome may burst and the enzyme digest their own cell.

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Lokmanya Dhankhar 7 years, 5 months ago

Because when a cell harmed by a thing and it go inside of a cell then the lysosomes digest that thing if it harms excess than the lysosomes brust and its enzymes digest its own cell

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Properties of electric field lines

Posted by Piyush Gupta 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 5 months ago

1. These are imaginary lines which shows pictorial influence of electric field intensity in space.
2. These are always emitted from positive charge and enter in negative charge.
3. They don't Form closed loops.
4. They are closely packed in strong electric field region and farther apart in weak electric field region.
5. These lines are always perpendicular to charsurface.
6. These lines never intersect with each other.

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Why do we fall ill ? Explain.

Posted by Hasmeet Khatri 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Debanshu Pradhan 7 years, 5 months ago

Because of not proper functioning of our body organs affected by many diseases .

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What are called canon rays

Posted by Saket Sahu 7 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Sahil Pilania 7 years, 5 months ago

Lbcxc

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Yogita Ingle 7 years, 5 months ago

Canal rays are radiations which are positively charged and was the key in the discovery of proton, another positively charged subatomic particle.
Its is also known as anode rays.
Its was invented by E. Goldstein in the year 1886.

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An object has moved through a distance. Can it have zero displacement? If yes,support your answer with an example

Posted by Shruti Kachchhi 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Kuldeep Choudhary 7 years, 5 months ago

Yes

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What is covalancy

Posted by G B 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 5 months ago

Covalency: The number of electrons that an atom can shared to get stable electronic configuration is called it covalency.

Ex: In order to get stable Neon gas configuration Carbon shares its four valence electrons. Thus its covalency is 4.

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A drive is able to cut through water in a swimming pool. Which property of matters does this observation show?

Posted by Aashu Behl 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Hasmeet Khatri 7 years, 5 months ago

This shows that the particles of matter have spaces between them

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What did happen when you put iron nail is copper Sulphate solution?

Posted by Aashu Behl 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Ashwini Ghorpade 7 years, 5 months ago

a redish brown colour appears

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Which precautions should be taken while preparing slide of onion peel? Write any two.

Posted by Aashu Behl 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 5 months ago

Precautions

Use a brush to transfer the peel from one apparatus to another.
Staining of peel should neither be too dark, nor too light.
Extra glycerine stain should be removed using blotting paper.

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Which phyulm does earthworm belong to? Write one main feature of this phyulm.

Posted by Aashu Behl 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 5 months ago

Earthworm belongs to annelida
Features are -

They are bilaterally symmetrical and triploblastic.
True body cavity is present in these animals.
The body is divided into segments and hence the name annelida.

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ANSWER

Which gas evolves when zinc metal is put into dilute sulphuric acid? Which test is done to confirm this gas?

Posted by Aashu Behl 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Ashwini Ghorpade 7 years, 5 months ago

all answers are in oswaal books

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(a) cell membrane is semi permeable. Explain.

Posted by Aashu Behl 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Ashwini Ghorpade 7 years, 5 months ago

Because it only allows entry of selected items in and out of the cell

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Give reasons (a) we spread out the cloths while putting them for dying. (b) we wear cotton clothes in summer.

Posted by Aashu Behl 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

G B 7 years, 5 months ago

A )because evaporation depends on surface area large surface area make evaporation faster and dry clothes B)because they have pores which help in evaporation

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Two objects, each of 1.5kg, are Moving in the same straight line but in opposite directions. The velocity of each object is 2.5m/s before the collision during which they stick together. What will be the velocity of the combined object after collisions.

Posted by Aashu Behl 7 years, 5 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

Write any three characteristics of colloids.

Posted by Aashu Behl 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 5 months ago

• A colloid is a heterogeneous mixture.
• The size of particles of a colloid is too small to be individually seen by naked eyes.
• Colloids are big enough to scatter a beam of light passing through it and make its path visible.
• They do not settle down when left undisturbed, that is, a colloid is quite stable.
• They cannot be separated from the mixture by the process of filtration. But, a special technique of separation known as centrifugation can be used to separate the colloidal particles.

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A car accelerates uniformly from 18km/h in 5km/h in 5s. Calculate (1)the acceleration and (2) the distance covered by the car in that time.

Posted by Aashu Behl 7 years, 5 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

What is composite fish culture? What are the advantages of composite fish culture?

Posted by Aashu Behl 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 5 months ago

In composite fish culture, several fast growing compatible fish species are grown together in a pond.

Advantages:

i) Maximum fish production is obtained in this method, with lesser cost.

ii) All ecological zones are exploited for achieving maximum yield.

iii) All available food in the pond is effectively utilised.

iv) The variety of fish produced is much higher as compared to monoculture.

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A constant forces acts on an object of mass 6kg for a duration of 3s. It increases the objects velocity from 3m/s to 9m/s. Find the magnitude of the applied force.

Posted by Aashu Behl 7 years, 5 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

What is the relation ship between "g" and "G" in gravitational chapter

Posted by Hamza Mohd 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 5 months ago

G stands for Newton's universal gravitational constant, whereas g stands for the acceleration due to gravity at a certain point.
G = 6.67300 × 10^-11 N.m².kg^-2. G is a constant throughout space and time.
g = 9.8 m.s^-2. g is a variable quantity.
G is a scalar quantity whereas g is a vector qualtity.
(According to Newton's law of universal gravitation the force of attraction between two bodies is given by F = GMm/r², where the symbols stand for their usual well known meanings. Also the weight of a body of mass m is F = mg.
So mg = GMm/r²,
or g = GM/r²
g is a constant at a given location, which depends upon M and r.)

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A bag of wheat weight 200 kg to what height it raice to so that its potential energy may be 9800 j

Posted by Hital Wadhwa 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Vidushi Sehrawat 7 years, 5 months ago

4.9m,but the answer change acc. To gravity i take 10 m

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Explain why explosion of a firework is said to be chemical change

Posted by Anushka Roy 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 5 months ago

Its chemical reaction as active chemicals get oxidised to rapid pace generating heat and sound. Cracker ingredients are enclosed in a tight pack so that when chemical reaction takes place the smoke and heat generated rips open the pack. Creates explosion.

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a ball weighing 4kg of density 4000kg /m^3 is completely immersed in water of density 1000kg/m^3 .find the buoyant force

Posted by Ekta Jain 7 years, 5 months ago

CBSE > Class 09 > Science