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Write two isotopes of hydrogen

Posted by Mohan Arya 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Anashuman Singh 7 years, 1 month ago

There are actually three: protium, deutrium and tritium.

2Thank You

ANSWER

"soil is formed by water" give reasons of your answer

Posted by Avi Kapoor 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Anashuman Singh 7 years, 1 month ago

When water flows through the rock crevices, it makes the cracks bigger. Also, when water left in these crevices freezes during the night, it breaks the rocks. Thus, water is also responsible for the formation of soil.

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What is the work to be done to increase the vilocity from 18km/hr to 19km/hr if the mass of the car is 2000kg.

Posted by Avi Kapoor 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Avi Kapoor 7 years, 1 month ago

How did you do this????

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Saloni Tak 7 years, 1 month ago

37000 J

3Thank You

ANSWER

Example of negative work??

Posted by Avi Kapoor 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Gaurav Seth 7 years, 1 month ago

Examples of Negative Work done
1. Someone pushes you
2. You are pulled from behind when you try to move front
3. In Arm wrestling, when someone is defeating you.
4. In Tug of War when opponent team pulls hard.
5. Pushing a car up a hill, when you slip back.
6. Trying to catch a heavy object, hands move down
7. When you jump, work done by gravity is negative
8. After you press a spring, it relaxes.
9. Trying to kick a moving football, work done by ball is negative
10. A car moving on road, work done by friction is negative

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ANSWER

Some fungal species live in permanent mutually dependent relationship with cyanobacteria?

Posted by Avi Kapoor 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Gaurav Seth 7 years, 1 month ago

1. Fungi are eukaryotic, non vascular, non-motile, heterotrophic organisms.
2. Their body is often composed of thread-like structures called hyphae. A web of hyphae is called mycelium.
3. The fungal cell wall is made up of chitin. The cells consist of a mass of cytoplasm embedded with numerous nuclei. The name for this condition is coenocytic and the organism is coenocyte.
4. The mode of nutrition is often parasitic, saprophytic or symbiotic.
5. They reproduce by means of sexual and asexual methods.

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ANSWER

What is animal husbandary??

Posted by Richa Kumari 7 years, 1 month ago

CBSE > Class 09 > Science

3 answers

Priyanshu Patel 7 years, 1 month ago

Take careing of animals for agricultural and economic utilization.

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Saloni Tak 7 years, 1 month ago

The breeding, rearing and feeding of domestic animals such as cattles is called animal husbandry

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Shivam Kumar 7 years, 1 month ago

The breeding and caring for farm animas is called animal husbandry.

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What happen to sugar when it is dissolved in water?where does it go? What information do you get about the nature of matter from rhe sugar in wale.

Posted by Avi Kapoor 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Saloni Tak 7 years, 1 month ago

The particles of water have space between them and the sugar particles get in it .This shows that matter have space between its particles.

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Nagaraj Raj 7 years, 1 month ago

There is particle size between them in the water then in which particles get it

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ANSWER

Sir pze tale me chapter 14 all cycles

Posted by Ramesh Kumar 29 7 years, 1 month ago

CBSE > Class 09 > Science

0 answers

ANSWER

What is drones

Posted by Naresh Kumar Kurmi 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Saloni Tak 7 years, 1 month ago

Drones are the male bees

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What is the si unit

Posted by Saddam Khan 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Anashuman Singh 7 years, 1 month ago

SI refers to "Systeme International". SI unit is the standard unit of any physical quantity.

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Give the reason when a car stops suddenly the patient in it tend to move forward

Posted by Ravi P 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Kamlesh Singh 7 years, 1 month ago

Due to inertia of motion Because when the car will in motion then passenger will also in motion then due to inertia of motion it will want to remain in motion 3if car will stop suddenly passenger will come forword

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What is the use of the valence electrons

Posted by Gyan Dev Bhardwaj 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Gyan Dev Bhardwaj 7 years, 1 month ago

They help in chemical reaction

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ANSWER

What is a negative work

Posted by Vinod Rai 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Kamlesh Singh 7 years, 1 month ago

If work done opposite to direction of motion

1Thank You

Aditya Raghav 7 years, 1 month ago

If the force has a component in the direction opposite to the displacement ,the force does negative work.

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ANSWER

The radius of planet jupiter is 11 times the radius of the earth . Calculate the ratio of the volumes of jupiter and the earth . How many earths can jupiter accomodate ? ( hint : R of jupiter = 11R of earth , V = 4/3×22/7 × R cube )

Posted by Shubhi Rajoliya 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Gaurav Seth 7 years, 1 month ago

We know that the ratio of volumes of two spheres is the ratio of cubes of their radii.
Radius of Earth = R
Radius of Jupiter = 11R

It is clear that the Jupiter will accommodate 1331 earths.

1Thank You

Gaurav Seth 7 years, 1 month ago

Let, the radius of Earth be R units

So, Volume of Earth =  cubic units
Given, radius of Jupiter is 11 times the radius of Earth.

So, radius of Jupiter = 11 R units

Volume og Jupiter =  = cubic units

Now, the ratio of the volume of Jupiter and Earth is =  =



So, 1331 Earths can be accommodated in one Jupiter.

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ANSWER

Why cell is called the structural and functional unit of life ???

Posted by Priya Jain 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Srishti Agarwal 7 years, 1 month ago

Our body is made up of different types of cells that's why it is càlled the structural unit of life.Whithout a cell our body cannot function that's why it is called functional unit of life.

3Thank You

Gaurav Seth 7 years, 1 month ago

The cells are called as structural and functional units of a living body. Cells are structural unit as they form the structure of the organism. Cells combine to form tissues, which further combine to form organs, organs combine to form organic systems, which further combine to form organism. So, cell is the basic structural unit for all unicellular and multicellular organisms.

Some of the basic life processes or functions takes place in every cell to keep the organisms alive such as digestion, respiration, excretion, etc., whether it is a single-celled organism or multicellular organism. So, the cells are also called the functional unit of life owing to these processes.

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How does the energy enter in the biosphere??

Posted by Revathee Devi 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Gaurav Seth 7 years, 1 month ago

(i) Energy enters into the biosphere through the process of photosynthesis carried out by plants in the presence of sunlight. Then, it is transferred from one tropic level to next.

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Posted by Ayush Kumar 7 years, 1 month ago

CBSE > Class 09 > Science

0 answers

ANSWER

What is the use of glycerine in preparation of slide of onion peel

Posted by Gaurav Sharma 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Aditya Raghav 7 years, 1 month ago

Glycerine prevents peel from dryness.

1Thank You

Gaurav Seth 7 years, 1 month ago

Onion peel experiment is done its study the cell structure.

Glycerin is considered as a mounting agent while making a slide of onion peel.
It is a good hydrating agent.
It does not allow the specimen to dry out during the long duration of study.
It provides a wet medium for the stain so the cell structure can be easily studied.
It expels bubbles which may come during the mounting of the slide.

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in a office two tubelight of 40 watt,a fan of 75 watt and a cooler of 150 watts and a camera of 5 watts have been installed. all the appliances are used for daily 10 hrs. if the cost of 1 unit is 10 paise . calculate their daily and monthly bill for January.

Posted by Hardik Porwal 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Neha Bhagat 7 years, 1 month ago

Sorry its 837paise for January

0Thank You

Neha Bhagat 7 years, 1 month ago

27 paise

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ANSWER

What happens to the life of a cell if there is no Golgi apparatus

Posted by Sachin Singh 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Priyanshu Patel 7 years, 1 month ago

There's no repair for cell membrane.

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Revathee Devi 7 years, 1 month ago

If there was no golgi apparatus there will be no formation of lysosome and the products won't be despatched

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Calculate the time period of wave if the frequency is 25Hz

Posted by Shrey Naik 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Srishti Agarwal 7 years, 1 month ago

f =1/t 25 = 1/t t = 1/25 t =0.4 seconds

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ANSWER

How many electrons are present in na+

Posted by Mohan Arya 7 years, 1 month ago

CBSE > Class 09 > Science

3 answers

Priyanshu Patel 7 years, 1 month ago

As u see in neutral there is 11 but in +Na 10

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Aditya Raghav 7 years, 1 month ago

10 electrons becauce it is an ion

1Thank You

Shrey Naik 7 years, 1 month ago

11elctrons

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ANSWER

What are CFC ?

Posted by D.R Reshma 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Sachin Singh 7 years, 1 month ago

Chlorofluro carbons are that carbon which harm the ozone layer the ozone layer protect us from the harmful chemicals radiations which come from the sun. It causes many skin infection.

2Thank You

Sahil Kasana 7 years, 1 month ago

Cloro floro carbons

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ANSWER

Can we beleive this sample papers and last year papers

Posted by Neeraja Gajabinkar 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Shubhanshu Sahu 7 years, 1 month ago

Science imp question

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Anie Jain 7 years, 1 month ago

Yes ......

3Thank You

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Work done to change the velocity

Posted by Mukul Singh 7 years, 1 month ago

CBSE > Class 09 > Science

0 answers

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A bullet of mass 20g is horizontaly fured with a velocity 150m/s from a pistol of mass 2 kg . What is the recoil velocity of the pistol.

Posted by Aman Raza 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Nitin Jangra,?✌ 7 years, 1 month ago

M1=20g=0.002kg U1=0 at rest V1=150m/s M2=2kg U1=0at rest V1=? M1*U1+M2*U2=M1*V1+M2*V2 0.002*0+2*0=0.002*150+2*V2 0=0.3+2*V2 -0.3=2*V2 -0.3/2=V2 V2 =-0.15

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Ananya ✌ 7 years, 1 month ago

Read the last example of chapter. It can help you. And it's difficult to solve numericle question on this.

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Mention an organism which exhibits characteristic of both plant and animal?

Posted by Ayus Agarwal 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Revathee Devi 7 years, 1 month ago

Euglena

1Thank You

Aman Raza 7 years, 1 month ago

Picther plant may be

3Thank You

ANSWER

Define,pseudocoel

Posted by Ayus Agarwal 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 1 month ago

Pseudocoelomate - false body cavity between epidermis and gastrodermis.

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Derive the formula: K=1/2mv^2 where K is Kinetic energy

Posted by Paras Sharma 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Gaurav Seth 7 years, 1 month ago

Consider a body of mass "m" starts moving from rest. After a time interval "t" its velocity becomes V.
If initial velocity of the body is Vi = 0 ,final velocity Vf = V and the displacement of body is "d". ThenFirst of all we will find the acceleration of body.Using equation of motion2aS = Vf2 – Vi2
Putting the above mentioned values
2ad = V2 – 0
a = V2/2dNow force is given by
F = ma
Putting the value of acceleration
F = m(V2/2d)
As we know that
Work done = FdPutting the value of F
Work done = (mv2/2d)(d)
Work done = mV2/2
OR
Work done = ½ mV2Since the work done is motion is called "Kinetic Energy"
i.e.
K.E. = Work done
OR
K.E. =1/2mV2.

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Sahil Ransing 7 years, 1 month ago

W=f×s W=ma×v^2-u^2÷

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Give a method to separate different gases of air?

Posted by Ayus Agarwal 7 years, 1 month ago

CBSE > Class 09 > Science

3 answers

Gaurav Seth 7 years, 1 month ago

Separation of components of air by the process called fractional distillation: In this process, air is liquefied under high pressure. Then it is boiled and depending upon the boiling points of fractions (gases), the components are separated.