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A 8000 kg engine pulls a train of 5 wagons each of 2000 kg along a horizontal truck if the engine exerts a force of 40000 n and the truck offers a friction force of 5000 n then calculate the force of wagon 1 and 2

Posted by Kiranvir Kaur 3 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Sia ? 3 years, 3 months ago

The external force is only applied to waggon 1 directly. On the last four waggons, the net force is equal to the force added to waggon 2 by waggon 1.

Let us consider the acceleration of the wagons is a_w

35000 = 5m × a_w

a_w = 35000/5m

a_w = 35000/(5 × 2000)

a_w = 3.5 m/s²

Then the mass of the last four wagons can be considered as m_w

m_w = 2000 × 4

m_w = 8000 kg

Now let us calculate the net force on the last four wagons

F’ = m_w× a_w

F’ = 8000 × 3.5

F’ = 28000 N

∴ The force of wagon-1 on the wagon-2 is 28000N.

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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 Kamran Javid 3 years, 8 months ago

CBSE > Class 09 > Science

1 answers

Lavanya Singh 3 years, 8 months ago

Yes , zero displacement is possible if an object has moved through a distance. Suppose a body is moving in a a circular path and starts moving from point a and it returns back at same point after completing one revolution then the distance will be equal to its circumference while displacement will be zero.

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If there is 7 horse power in a lambourgini car . Then what's is the speed of this car?

Posted by Aayush Singh@8 3 years, 8 months ago

CBSE > Class 09 > Science

1 answers

Vidhi Agarwal 3 years, 8 months ago

?????mtlb kuch b..

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Broucher on sikkim project

Posted by Hema Gupta 3 years, 8 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

Define momentum and state its S.I unit.

Posted by Navjot Kaur 3 years, 8 months ago

CBSE > Class 09 > Science

3 answers

Adhish Annamalai 3 years, 8 months ago

Momentum: The momentum of an object is the product of its mass and velocity and have the same direction as that of the velocity. SI unit of Momentum: It's SI UNIT is Kg m s^-2

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Aneesha Jat 3 years, 8 months ago

I don't know

1Thank You

Swati ? 3 years, 8 months ago

The Product of mass and velocity is called momentum and its S.I unit is kg.m/s(kilogram meter per second) .

4Thank You

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What is health in ch-13 class 9th

Posted by Mohit Rathi 3 years, 8 months ago

CBSE > Class 09 > Science

3 answers

Bharti Yadav 3 years, 8 months ago

The state of being physically, mentally or socially well being

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Dilpreet Malhans 3 years, 8 months ago

Health is jaan

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Shine Rai 3 years, 8 months ago

The state of being physically, mentally or socially fit

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In every question of work and energy thita will be given.

Posted by King Abbeee 3 years, 8 months ago

CBSE > Class 09 > Science

2 answers

Prince Raj 3 years, 8 months ago

When At certain angle

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Amarjeet Kumar 3 years, 8 months ago

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What is hybridization and define it's types?

Posted by Khushi Parveen 3 years, 8 months ago

CBSE > Class 09 > Science

5 answers

Adhish Annamalai 3 years, 8 months ago

Hybridization: Hybridization is the concept of mixing atomic orbitals into new hybrid orbitals (with different energies, shapes, etc., than the component atomic orbitals) suitable for the pairing of electrons to form chemical bonds in valence bond theory. Types of Hybridization: Based on the types of orbitals involved in mixing, the hybridization can be classified as sp3, sp2, sp, sp3d, sp3d2, sp3d3.

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Khushi Parveen 3 years, 8 months ago

In plants ??

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Alex Jender 3 years, 8 months ago

Hii

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Aneesha Jat 3 years, 8 months ago

hybridization is the concept of mixing atomic orbitals into new hybrid orbitals (with different energies, shapes, etc., than the component atomic orbitals) suitable for the pairing of electrons to form chemical bonds in valence bond theory.

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Nitya Gupta 3 years, 8 months ago

1Thank You

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Define Cillia

Posted by Rudra Thakkar 3 years, 8 months ago

CBSE > Class 09 > Science

2 answers

Roshni Rout 3 years, 8 months ago

If you only want the defination of cilia then, Small hair like projections are called cilia.

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Parisha Rukhaya 3 years, 8 months ago

Small thread like structures present on the free surface of ciliated cuboidal & ciliated columnar cells.

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What are the properties of suspension?

Posted by Sabreen Sabreen 3 years, 8 months ago

CBSE > Class 09 > Science

5 answers

Swati ? 3 years, 8 months ago

1.Suspension is a hetrogeneous mixture. 2. Particles of suspension are visible to naked eys. 3. Diameter of particle is 100nm (1nm=10^-9m). 4. It is unstable.

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Chaudhary Vineet 3 years, 8 months ago

1.Suspension is a heterogeneous mixture 2.the partical size of suspension is more the 10^5 3.suspension show Tyndale effect 4. solute particles settle down when we left undisturbed 5. they are filter by filter paper

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Nitya Gupta 3 years, 8 months ago

1. Suspension is a heterogeneous mixture. 2. The particles of a suspension can be seen by the naked eye. 3. The particles of a suspension scatter a beam of light passing through it and make its path visible. 4. The solute particles settle down when a suspension is left undisturbed, i.e. a suspension is unstable. They can be separated from the mixture by the process of filtration. When the particles settle down, the suspension breaks and it does not scatter light anymore.

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Himanshu Gupta 3 years, 8 months ago

Xhn

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Adarsh Patil 3 years, 8 months ago

They are notstable They are heterogeneous mixture They can be seen by naked eyes

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What was the model of an atom proposed by Thomson

Posted by Damini Damini 3 years, 8 months ago

CBSE > Class 09 > Science

1 answers

Sawan Ahlawat 3 years, 8 months ago

The modal proposed by Thomsan showed that there is solid positive nucleus present inside the atom and except nucleus whole atom is negatively charged. He showed it by passing Alpha rays from from thin gold sheet he noticed that most of rays which were passing through the gold sheet were getting deflected with very small angle and many few were passing straight and even very very few rays were getting deflected by 180°.

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Explian why is it biffcult for a fireman to hold a house which ejects large amounts of water at a high velocity

Posted by Lisa Lisa 3 years, 8 months ago

CBSE > Class 09 > Science

1 answers

Nitya Gupta 3 years, 8 months ago

When fireman directs a large amount of water at a high velocity on fire from a hose pipe, they have to hold the hose pipe strongly because of its tendency to go backwards. The backward movement of the hose pipe is due to the backward reaction force of water rushing out through it in the forward direction at a high speed as per the Newton's third law of motion

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Which of the following electronic configuration is not possible. Give reason. i) A : 2,8,7 ii) B: 3,8,7

Posted by Kanmani Vedham 3 years, 8 months ago

CBSE > Class 09 > Science

5 answers

Dilpreet Malhans 3 years, 8 months ago

Lun

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Chaudhary Vineet 3 years, 8 months ago

2 is not possible because the energy lv. of k shell have to take only two electrons and in 2 option give that k shell have 3 electro we find the energy lv. by the formula of 2n^2. where n is the shell no. May it help you....

1Thank You

Nitya Gupta 3 years, 8 months ago

0Thank You

Aditya Singh 3 years, 8 months ago

1Thank You

Tanish Jain 3 years, 8 months ago

0Thank You

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what is decantation

Posted by Tushar Chettri 3 years, 8 months ago

CBSE > Class 09 > Science

1 answers

Aditya Singh 3 years, 8 months ago

It is a process for the separation of mixtures of immiscible liquids or of a liquid are a solid mixture such as a suspension

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ANSWER

technique which is used to separate immiscible liquid

Posted by Tushar Chettri 3 years, 8 months ago

CBSE > Class 09 > Science

4 answers

Virat Singh 3 years, 8 months ago

Decantation

1Thank You

Parisha Rukhaya 3 years, 8 months ago

Using separating funnel

2Thank You

Sabreen Sabreen 3 years, 8 months ago

Decandation

1Thank You

Tushar Chettri 3 years, 8 months ago

decantation

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name the technique which is used to separate dye from black ink.

Posted by Tushar Chettri 3 years, 8 months ago

CBSE > Class 09 > Science

5 answers

Chaudhary Vineet 3 years, 8 months ago

CHROMATOGRAPHY

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Nitya Gupta 3 years, 8 months ago

Chromatography

0Thank You

Virat Singh 3 years, 8 months ago

Chromatography

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Esha Mittal 3 years, 8 months ago

chromatography

0Thank You

Tushar Chettri 3 years, 8 months ago

chromatography

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why gravitational force is usually unnoticeable

Posted by Damini Damini 3 years, 8 months ago

CBSE > Class 09 > Science

2 answers

Nitya Gupta 3 years, 8 months ago

The gravitational force works on the mass of the body it's not an any object we can only feel it

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Himanshi Sahu 3 years, 8 months ago

The strength of gravity depends on the masses of each object and also distance between them. All objects experience an attraction toward all other objects. But earth's mass is so large it makes gravitational pull of all other objects on Earth unnoticeable.

3Thank You

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Give me some examples of greenhouse effect

Posted by Rohan Solanki 3 years, 8 months ago

CBSE > Class 09 > Science

2 answers

Virat Singh 3 years, 8 months ago

Water vapour ,carbon dioxide , chlorofluorocarbons, methane,ozone ,nitrous oxide

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Tiger ? 3 years, 8 months ago

Water vapor, Carbon dioxide, Methane, Ozone, Nitrous oxide, Chlorofluorocarbons .

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Give five examples of an object gets displaced in the absence of force acting on it

Posted by Arpita Nehra 3 years, 8 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

Explain the nitrogen cycle in point wise ?

Posted by Hasina Mandar 3 years, 8 months ago

CBSE > Class 09 > Science

2 answers

Nitya Gupta 3 years, 8 months ago

1. Nitrogen fixation 2. Nitrification 3. Assimilation 4. Ammonification 5. Denitrification

1Thank You

Nitya Gupta 3 years, 8 months ago

Nitrogen Cycle is a biogeochemical process which transforms the inert nitrogen present in the atmosphere to a more usable form for living organisms

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There are two bodies having equal masses are moving with uniform speeds of v and 2v respectively . Find the ratio of their kinetic energies .

Posted by Tiger ? 3 years, 8 months ago

CBSE > Class 09 > Science

1 answers

Himanshi Sahu 3 years, 8 months ago

Hence. ratio of their kinetic energies is: k2k1=v22v12=(2v)2v2=2v2v2=41=1:4.

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How does evopration causes ?

Posted by Nisha Murali 3 years, 8 months ago

CBSE > Class 09 > Science

3 answers

Nitya Gupta 3 years, 8 months ago

When water gets its boiling point 100⁰C then the water started to convert into vapours

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Virat Singh 3 years, 8 months ago

Evaporation caused by heat

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Aditya Singh 3 years, 8 months ago

Heat cause evaporation

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What is the function of genes in an organisms

Posted by Diksha Verma 3 years, 8 months ago

CBSE > Class 09 > Science

1 answers

Nishtha Bhargava 3 years, 8 months ago

All living beings have genes. They exist throughout the body. Genes are a set of instructions that determine what the organism is like, its appearance, how it survives, and how it behaves in its environment.

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which of the following is not a viral deasease 1. Dengue 2.Typhoid 3.Aids 4.Influenza

Posted by Mohd_Affan_ Saifi?? 3 years, 8 months ago

CBSE > Class 09 > Science

5 answers

Nisha Murali 3 years, 8 months ago

Aids is not a viral deseases .

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Nisha Murali 3 years, 8 months ago

Influenza

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Japnidh Kaur 3 years, 8 months ago

Option A. Dengue: It is a viral disease which is caused by the bite of infected Aedes species. The person being affected the second time is at risk of developing severe disease. The symptoms include high fever headache, rash, joint pain etc, there are medications for dengue. > Option B. AIDS: It is a sexually transmitted viral disease. Acquired immune deficiency syndrome is caused by HIV - human immunodeficiency virus. The initial stages are sometimes difficult to detect as it includes flu like illness. But gradually there are large lymph nodes, welght loss etc. It is caused by any kind. of physical contact with the diseased. > Option C. Typhoid: It is a fever that spreadsthrough contaminated food or water. It is a common disease. It has symptoms like headache, stomach pain, vomiting etc. It is caused by the Salmonella species. > Option D. Influenza: It is a viral disease caused by the influenza virus. It Infects the nose, throat, lungs of the patient. It can spread when the diseased person sneezes, coughs or talks. So the answer is option C: Typhoid

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Kashvi Swaroop 3 years, 8 months ago

Aids is not a viral disease.

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Mohd_Affan_ Saifi?? 3 years, 8 months ago

plzz answer me

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Ques. 2) A mass of 10 kg is at a point A on a table. It is moved to a point B. If the line joining A and B is horizontal, what is the work done on the object by the gravitational force? Explain your answer.

Posted by Riya Sharma💜🤞 3 years, 8 months ago

CBSE > Class 09 > Science

5 answers

Pallavi Bharti 3 years, 8 months ago

The work done is zero as the angle between force and displacement is 90 degree

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Virat Singh 3 years, 8 months ago

The w********

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Adarsh Patil 3 years, 8 months ago

The work done by gravity is reducing the friction As we know about friction is reduce air and makes hard to push the the object therefore gravity made excellent work

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Mohd_Affan_ Saifi?? 3 years, 8 months ago

f***

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Nitesh Punera 3 years, 8 months ago

Hello

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Ques.1) A Certain force acting on a 20 kg mass changes its velocity from 5 ms -1 to. Calculate the work done by the force.

Posted by Riya Sharma💜🤞 3 years, 8 months ago

CBSE > Class 09 > Science