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Thomsan proposed a model of an atom to be similar like a Christmas pudding. The electrons ,in a sphere of positive charge ,were like dry fruits in a spherical Christmas pudding. He also comared watermelon, the positive charge in an atom is spread red edible part of watermelon, while electron are studded in positively charged sphere like the seeds of watermelon

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Vishal Rajput 7 years, 1 month ago

This model is often called the 'Water Melon Model'

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what does silver revolution refers to

Posted by Chinnegowda Chinnegowda 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Himanshu Kumar 7 years, 1 month ago

It refers to the increase in production of eggs by help of medical science

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What are the characteristics of agaricus

Posted by Harit Naagar 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Dollsi Jain 7 years, 1 month ago

sorry not in plante kingdom

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Dollsi Jain 7 years, 1 month ago

these are hetrotrophic eukaryotic org they feed on dead and decaying organisms and they are called saprophytes they have the ability of become multicellular organisms at some stage of life they have cell wall made up of tough complex sugar called chitin. they reproduce by both sexual and asexual mode of reproduction expamle agaricus ( mushroom) they are also called fungi or they are included in the group of fungi in plante kingdom

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A train starting from rest attains a velocity of 72 km / h in 5 minute. Assuming that the acceleration is uniform, find the distance travelled by the train for attaining this velocity

Posted by ??? ???? 7 years, 1 month ago

CBSE > Class 09 > Science

0 answers

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What is mass on electron

Posted by Abhi Sharma 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Akanksha Kumari? 7 years, 1 month ago

Relative mass of electron is 1/ 1836 u. Absolute mass of an electron is 9 × 10^ -28 g.

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What is scum

Posted by Abhay Walia 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Meghna Thapar 6 years, 1 month ago

Scum is a layer of unpleasant or unwanted material that has formed on the top of a liquid.

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What came first egg or hen.

Posted by Sahil G 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

??? ???? 7 years, 1 month ago

First egg came

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Ria Bansal 7 years, 1 month ago

egg came first because u didn’t specify weather u are talking about hen’s egg or dinosaur so dinosaurs egg came before hen

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Relationship between g and G

Posted by Swayam Gupta 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Studies 1 7 years, 1 month ago

G is the gravitational constant = 6.673×10^-11 N m^2/kg^2 And g is the accelerarion caused by gravity to any object in free fall , it is 9.8 m/s^2

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Rishav Thakur 7 years, 1 month ago

Relation between g and G is given below g=GM/R^2 OR Small (g) is equal to the product of G and mass divided by radius square

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How can we separate cream from milk?

Posted by Shaik Saniya 7 years, 1 month ago

CBSE > Class 09 > Science

3 answers

Rishav Thakur 7 years, 1 month ago

Sorry by centrifugation

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Rishav Thakur 7 years, 1 month ago

By gentrification In the machine is rotated at high speed and heavier particle called in local language as lassi settle down and the cream floats on it this is the whole process of separation

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Sahil Nandode 7 years, 1 month ago

By centrifugation

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What would be the effect of density on the rate of diffusion of liquids?

Posted by Yashwanth R 7 years, 1 month ago

CBSE > Class 09 > Science

3 answers

Aditya Raghav 7 years, 1 month ago

High density of liquids means ,kinetic energy of liquid decreases. If the energy is decreases the rate of diffusion also decreases.

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Studies 1 7 years, 1 month ago

The denser the liquid diffusion would be slower. As density is defined as mass per unit volume i.e. Density = M/V The more the mass and the less the volume together diffusing rate of the liquids would decrease.

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Yashwanth R 7 years, 1 month ago

Can I get the answer soon, its little urgent please

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Usha swims in a 90m long pool. She covers 180m in one minute by swimming from one end to other end to the other and back along the same straight path. Find the average speed and average velocity of Haha.

Posted by ??? ???? 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Studies 1 7 years, 1 month ago

Given : s = 90m Total s=180 m To find : avg. Vel and avg.speed Formula :avg speed = totaldistance/total time taken avg Vel = displacement/time Solution : avg speed = 180/60s = 3m/s As for avg.vel as the displacement is zero the avg vel = 0m/s

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Why the temperature remains constant during sublimation

Posted by Deepak Swain 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Yogita Ingle 7 years, 1 month ago

Temperature remains constant while sublimation because the heat energy gets converted into latent heat of vaporisation. the heat energy is used up to overcome the molecular force of attraction thus,the temp. remains constant.

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Vaishali Darandale 7 years, 1 month ago

Simple same

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Featers of mangrove forest

Posted by Sagar Chand 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 1 month ago

Mangrove forests are found in Ganga-Brahmaputra delta, Krishna, Kaveri, Godavari and Mahanadi delta.
Characteristics of these forests are as follows
(i) Roots of these plants remain submerged under water.
(ii) The tree species can tolerate high salt concentration.
(iii) Roots develop preumatophars or aerial root for sucking oxygen.

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What is bionomen nomleclatute

Posted by Kalyani Teacher☺ 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Yashwanth R 7 years, 1 month ago

Binomial Nomenclature --- is a system of scientific naming of the vast diversity of life around us. It consists of two words --- a generic name and a specific name.

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Meenakshi Maheswari 7 years, 1 month ago

Scientific names

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Name three stages in which farming practice divided

Posted by Muqueet Faraz Cbr 7 years, 1 month ago

CBSE > Class 09 > Science

0 answers

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Define potential energy. What are the differences type of potential energy

Posted by Pranjal Amrutfale 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Yogita Ingle 7 years, 1 month ago

Potential energy is the energy stored in a body due to its position or configuration.
e.g. gravitational potential energy, elestic potential energy, electrostatic potential energy, magnetic potential energy, chemical energy. Any stored energy can be called the potential energy and it has the potential to do work.
Examples of potential energy:
1. When we wind up the spring of a toy car using a key, our muscular energy is stored in its spring. When this elastic potential energy is released the toy car moves.
2. A stone placed at a height, water stored high up in the dams, etc. have gravitational potential energy.

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Kalyani Teacher☺ 7 years, 1 month ago

The enery possedby an object which is in rest or at a certain height

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How does industrylization

Posted by Bilalsha Rajesha 7 years, 1 month ago

CBSE > Class 09 > Science

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Tabulate the difference between states of matter

Posted by Himanshu Namdev 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Arpit Jindal 7 years, 1 month ago

Solid, liquid and gas Solid= It has definite shape and volume. The particles are tightly packed. Liquid= It has not definite shape and volume. The particles are intermediate. Gas= It has neither definite shape nor definite volume. The particles are very loosely packed.

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What is agronomy

Posted by Harsh Shah 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Amidhi Jain 7 years, 1 month ago

Agronomy (from Ancient Greek ἀγρός agrós "field" and νόμος nómos "law") is the science and technology of producing and using plants for food, fuel, fiber, and land reclamation. Agronomy has come to encompass work in the areas of plant genetics, plant physiology, meteorology, and soil science. It is the application of a combination of sciences like biology, chemistry, economics, ecology, earth science, and genetics. Agronomists of today are involved with many issues, including producing food, creating healthier food, managing the environmental impact of agriculture, and extracting energy from plants.[1] Agronomists often specialise in areas such as crop rotation, irrigation and drainage, plant breeding, plant physiology, soil classification, soil fertility, weed control, and insect and pest control.

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Who discovered cosmos

Posted by Ashish Shukla Boss 7 years, 1 month ago

CBSE > Class 09 > Science

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What is the greenhouse effect

Posted by Rohit Gour 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Dharshan Yadav 7 years, 1 month ago

The gases like carbon dioxide methene nitrate oxides prevent the escape of heat from the surface of the Earth by trapping it. This increases average temperature of the earth This is called green house effect

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What are the limitations of rutherford model

Posted by Sahil Jain 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 1 month ago

Limitations of Rutherford’s Model:
• The orbital revolution of the electron is not expected to be stable.
• According to Rutherford’s model, the electrons, while moving in their orbits, would give up energy.

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Are vaccination and immunization different terms? If yes what is the difference?

Posted by Arya Magade 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 1 month ago

Vaccination	Immunization
The process involves Introducing a weakened / deactivated disease causing microbes into a person	The process starts after the person is exposed to the vaccine and the body starts building resistance to that disease
It is usually injected or administered orally	It is not administered in any way, the body develops the resistance from vaccines
Imovax Rabies is the trade name for rabies vaccine	The body builds up immunity through this vaccine for the disease rabies
Vaccination does not guarantee complete resistance to a disease	Complete immunity occurs when the person fully recovers from the disease
Usually, if mutation happens to microbe, it might render the vaccine ineffective (this is the reason why common cold has no vaccine)	Similarly, variations of a disease impact the body’s ability to generate an immune response

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What is the difference between mechanical sound wave and longitudinal sound wave?

Posted by Arya Magade 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

??? ???? 7 years, 1 month ago

Mechanical wave : The wave which require a medium to travel is known as mechanical wave. Longitudinal wave : Wave motion and particle motion and wave propagation are in same direction is known as longitudinal wave.

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What is the difference between organ specific and tissue specific diseases?

Posted by Arya Magade 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 1 month ago

The major difference between organ specific and tissue specific manifestation lies within the different microbes which target various tissues or organs.
For example, in case of tuberculosis, the bacteria targets a specific organ i.e., lungs, through which the disease spreads in the body.
On the other hand, in case of malaria, the infection spreads through the blood. The causal organism targets the tissue i.e. blood, for spreading the disease in the body.

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How to convert Km/h into m/sec

Posted by ??? ???? 7 years, 1 month ago

CBSE > Class 09 > Science