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a girl of mass 50 kg jumps out of a rowing boat of mass 300 kg with velocity of 2m/s.at which velocity the boat moves backwards

Posted by Pradeep Mehta 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Sarita Panda 5 years, 3 months ago

With 1 m/s (approx)...

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What is main factor of solid liquids and gas

Posted by Lovely Yadav 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Meghna Thapar 5 years, 3 months ago

Two factors determine whether a substance is a solid, a liquid, or a gas: The kinetic energies of the particles (atoms, molecules, or ions) that make up a substance. Kinetic energy tends to keep the particles moving apart. The attractive intermolecular forces between particles that tend to draw the particles together. A solid has definite volume and shape, a liquid has a definite volume but no definite shape, and a gas has neither a definite volume nor shape. The change from solid to liquid usually does not significantly change the volume of a substance.

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What is different between mirror and image

Posted by Lovely Yadav 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Meghna Thapar 5 years, 3 months ago

A mirror is typically made of glass with a shiny metal backing that reflects all the light that strikes it. When a mirror reflects light, it forms an image. An image is a copy of an object that is formed by reflection or refraction. Mirrors may have flat or curved surfaces. In two dimensions. In geometry, the mirror image of an object or two-dimensional figure is the virtual image formed by reflection in a plane mirror; it is of the same size as the original object, yet different, unless the object or figure has reflection symmetry

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What are the advantages of classifying organisms.

Posted by Riya Mangang 5 years, 3 months ago

CBSE > Class 09 > Science

4 answers

Sanskar Shukla 5 years, 3 months ago

Any other doubt you have then tell me

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Riya Mangang 5 years, 3 months ago

Thanks

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Sanskar Shukla 5 years, 3 months ago

And this is one of the advantage

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Sanskar Shukla 5 years, 3 months ago

There are millions of organisms on earth so the study of each individual is almost impossible that why the classification of organisms are important

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Write two characteristic features of kingdom fungi that distinguish it from other kingdoms

Posted by Tamas Kori 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Meghna Thapar 5 years, 3 months ago

These organisms are classified as a kingdom, which is separate from the other eukaryotic life kingdoms of plants and animals. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. The cell wall of most of the members of kingdom fungi is made up of chitin. They are heterotrophic (parasitic and saprophytic). They have a eukaryotic cell and are mostly multicellular (exc: Yeast). They reproduce through various different types of spores produced in fruiting bodies.

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Describe in a brief about momentum

Posted by Nanthithaa Varshini 5 years, 3 months ago

CBSE > Class 09 > Science

2 answers

Deepika R 5 years, 3 months ago

Momentum is the product of mass and velocity. Si unit of momentum is kg m/s. p=m X v. Momentum is directly proportional to mass and velocity.

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Sanskar Shukla 5 years, 3 months ago

Momentum means the product of mass and velocity of an object

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In chapter: Motion how to find that for which question what equations of motion to use?????

Posted by Nanthithaa Varshini 5 years, 3 months ago

CBSE > Class 09 > Science

3 answers

Mishika Pandey 5 years, 3 months ago

When you start solving first write given and then write eq in side and compare given with eqs

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Samruddhi Ghodke 5 years, 3 months ago

Logically as per me...!

4Thank You

Aditi.T Rajesh 5 years, 3 months ago

Make a note of the quantities and then see which equation is related to those quantities. We can get to know by this method

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What is the meaning of velocity

Posted by Satya Jiban 5 years, 3 months ago

CBSE > Class 09 > Science

3 answers

Harman Kaur 5 years, 3 months ago

Velocity is the displacement upon time and it is and vector quantity because placement is a vector it has its own magnitude and depends on direction so this much

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Dev Thakkar 5 years, 3 months ago

★Velocity is the vector quantity which depends upon the direction of motion. ★It can be zero, positive or negetive. ★We can find the velocity by displacement divided by taken time.

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Nanthithaa Varshini 5 years, 3 months ago

Smallest : Sperm Biggest : Ovum

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Name the smallest and the biggest cell in human body

Posted by Deepansh Awasthi 5 years, 3 months ago

CBSE > Class 09 > Science

5 answers

Manoj Tomar 5 years, 3 months ago

The smallest cell in the human body RBC and the largest cell in human body ovum?????

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Sanskar Shukla 5 years, 3 months ago

First one is correct

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Vandana Rustagi 5 years, 3 months ago

Smallest is RBC and largest is nerve cell

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Divya Gupta 5 years, 3 months ago

Smallest is sperm and biggest is ovum

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Satya Jiban 5 years, 3 months ago

Sir i don't know

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Chapter 14 natural resources will be assessed or not

Posted by Tripti Shrimali 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Lovely Yadav 5 years, 3 months ago

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What are the limitations of J.J Thomson's model of the atom?

Posted by Arnav Sharma 5 years, 3 months ago

CBSE > Class 09 > Science

2 answers

Dev Thakkar 5 years, 3 months ago

Thomson's atomic model failed to explain how the positive charge holds on the electrons inside the atom. It also failed to explain an atom's stability. The theory did not mention anything about the nucleus of an atom. It was unable to explain the scattering experiment of Rutherford.

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Satya Jiban 5 years, 3 months ago

electron,proton

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What Is the force of attraction between earth and a man of mass 50kg M1=50 kg M2=6.6×10^24 R= 6.4×10^6

Posted by M. Harsha Vardhan 5 years, 3 months ago

CBSE > Class 09 > Science

2 answers

Sanskar Shukla 5 years, 3 months ago

You can get the answer by the formula--F=GM1*m2/Rsquare

1Thank You

Satya Jiban 5 years, 3 months ago

Gravitation

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A body of mass 5kg is moving with a velocity of 10m/s. A force is applied to it so that in 25seconds, it attains a velocity of 35m/s. Calculate the value of the force applied

Posted by Naziya Ppns 5 years, 3 months ago

CBSE > Class 09 > Science

2 answers

Sanskar Shukla 5 years, 3 months ago

5 Neuton is the answer

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Riya Mangang 5 years, 3 months ago

F=ma m=5kg, a=(35m/s-10m/s)/25 =25/25 =1 F=5*1 =5N

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Define osmosis.what happens when a plant cell is put into a hypertonic medium ??

Posted by Sumi Deep 5 years, 3 months ago

CBSE > Class 09 > Science

2 answers

Nanthithaa Varshini 5 years, 3 months ago

Osmosis is the the process of solvent moving from lower concentration to higher concentration. It requires a semi permeable membrane. When the cell is placed in a hypertonic solution water does moves out of the cell andnit gets shrinked

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Alok Gupta 5 years, 3 months ago

Osmosis is the spontaneous net movement of solvent molecules through a selectively permeable membrane into a region of higher solute concentration, in the direction that tends to equalize the solute concentrations on the two sides. When a plant cell is placed in a solution that is hypertonic relative to the cytoplasm, water moves out of the cell and the cell shrinks.

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Defin the term "chemically pure substances"?

Posted by Nandita Bhoy 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 5 years, 3 months ago

Pure substances are substances that are made up of only one kind of particles and has a fixed or constant structure.

Pure substances are mostly homogeneous in nature containing only one type of atoms or molecules.
These substances mainly have a constant or uniform composition throughout.
The substances have fixed boiling and melting points.

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I have some silly doubts in third chapter atoms and molecules plz clarify it - how can we write the formulas of any compounds whenever I have not given their chemical name instead given their commonly name .?? Like - write the formula of sea salt ???if u feel that this is a stupid question then do not give answer???

Posted by Palak Pandey 5 years, 3 months ago

CBSE > Class 09 > Science

5 answers

Palak Pandey 5 years, 3 months ago

This is not enough plz read full ??

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Aditi.T Rajesh 5 years, 3 months ago

The formula for sea salt is NaCl. Similarly, baking soda is also sodium bicarbonate,i.e.,NaHCO3

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Priyanka Sahni 5 years, 3 months ago

Me too have so many doubts in chapter 3

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Chandni Sehajpal 5 years, 3 months ago

Your questions is not stupid I have also problems in formulas

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Chandni Sehajpal 5 years, 3 months ago

3 chapter sanu karvaya nahe va

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My exams are near how to manage time for each subject

Posted by Mishika Pandey 5 years, 3 months ago

CBSE > Class 09 > Science

2 answers

Harshika Yadav 5 years, 3 months ago

Sabhi ko ak ak karka padho???

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A C 5 years, 3 months ago

Sabhi ko half an hour do

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science chp.10 class 9 (physics ) example 10.1

Posted by Tutul ?? 5 years, 3 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

What is the use of valency

Posted by Abhinav Yadav 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Emiway X Gaming 5 years, 3 months ago

The number of electrons present in the outer layer of an atom is known as its valency

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What magnitude

Posted by Sarvesh S Subramanian 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 5 years, 3 months ago

Magnitude of a physical quantity tells us about the quantity of the physical quantity
(i.e., How much of the physical quantity)
Example: If we say a displacement 500 m. It does mean that distance is measure in metre, but how many metres?
500. So this 500 is the magnitude in case of displacement 500 m.

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What is Funga

Posted by A B 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 5 years, 3 months ago

The organisms belonging to this group are heterotrophic (Consume the food from the environment) eukaryotic organisms.
The organisms belonging to this group consume decaying organic material as food. Therefore they are called saprophytes.
These organisms can become multicellular organisms at specific stages of their lives.
The cell-walls of these organisms are made of a tough complex sugar called chitin.
Examples of organisms belonging to this group are yeast and mushrooms.

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Why the life does not exist on venus and Mars?

Posted by Tandel Tejal Rajeshkumar 5 years, 3 months ago

CBSE > Class 09 > Science

5 answers

Sanskar Shukla 5 years, 3 months ago

There is no gravity, oxygen and something else in Mars and venus and also they are very close to sun ☀

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Radha Kothari 5 years, 3 months ago

Because Mars and Venus are very close to sun thatswhy they are hot ? and water doesn't exist on the planets

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Abhishek Chaudhary 5 years, 3 months ago

Because Venus and Mars ara hot planet and the isn't exit on both planet

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Anurag Rawat 5 years, 3 months ago

Because Venus and Mars don't found water .

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Raj Baibhav 5 years, 3 months ago

Because of the hottest on these planet by the sun

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Name the different types of plastids and explain their functions ??

Posted by Sumi Deep 5 years, 3 months ago

CBSE > Class 09 > Science

2 answers

Abhishek Chaudhary 5 years, 3 months ago

Three types of plastids are: 1. Chloroplast = it has green colour pigment called chlorophyll which is essential for photosynthesis . 2 . Chromoplast = it helps to give colour to the parts of the plants. For ex =flowers and friut . 3 . Leucoplast = it is a colorless plastid which helps to store like carbohydrates and protein.

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Muskan Singh 5 years, 3 months ago

Three types of plastids are Chloroplast Chromoplast Leucoplast 1. Chloroplast = It has green colour pigment called chlorophyll which is essential for photosynthesis. 2. Chromoplast = It contain colourful pigments . These are found in the colourful parts of plant such as flower and fruits. 3. Leucoplast = It is a colourless plastid and the food like carbohydrate, protein are stored in it.

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When 3.0 g of carbon is burnt in 8.00g oxygen, 11.00g of carbon dioxide is produced . What mass of carbon dioxide Will be formed when 3.00g of carbon is burnt in 50.00 g of oxygen ? Which law of chemical combination will govern your answer ?

Posted by Muskan Singh 5 years, 3 months ago

CBSE > Class 09 > Science

2 answers

Muskan Singh 5 years, 3 months ago

How

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Sarita Panda 5 years, 3 months ago

11grams, law of constant proportional.

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Difference between magnitude and velocity?

Posted by Utkarsh Sharma 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Riya Mangang 5 years, 3 months ago

Magnitude is the numerical value of a given vector quality. Velocity is distance travelled by the body per unit time in a given direction.

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Who is the father of biology????

Posted by Palak Pandey 5 years, 3 months ago

CBSE > Class 09 > Science

5 answers

Yuvika Gupta 5 years, 3 months ago

Aristotle

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Anurag Rawat 5 years, 3 months ago

Aristotle

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Bhawna Jain 5 years, 3 months ago

Aristotle

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Yogita Ingle 5 years, 3 months ago

Aristotle is known as the Father of Biology.

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Muskan Singh 5 years, 3 months ago

Aristotle

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How can parts of major groups of activities for improving crop yields can be classified as

Posted by Kevin Pandya 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 5 years, 3 months ago

(i) Crop production management
(ii) Crop improvement
(iii)Crop protection management

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If z=3,what would be the valancy

Posted by Dhairya Chitransh 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 5 years, 3 months ago

By Z = 3, we mean that the atomic number of the element is 3. Its electronic configuration is 2, 1. Hence, the valency of the element is 1 (since the outermost shell has only one electron). Therefore, the element with Z = 3 is lithium.

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A girl of mass 40kg jumps with a horizontal velocity of 5 ms^-1onto a stationary cart with frictionless wheels.The mass of cart is 3kg. What is her velocity as the cart starts moving?Assume that there is no external unbalanced force working in the horizontal direction.

Posted by Charming Princess? 5 years, 3 months ago

CBSE > Class 09 > Science