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Mechanical energy is the energy that is linked with the motion of an object. This energy is usually stored in an object so that it can enable it do work once force is applied to it.
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Mechanical energy is a kind of energy created by the physical movement or rotation, revolution etc of anything.Since most of the movements done and energy created are done by machines, it is named as mechanical energy.

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Rutherford's model of drawback

Posted by Ranjeet Yadav 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Vijayalakshmi J 7 years, 4 months ago

Rutherford's model could not explain the stability of an atom. If electrons moves around the nucleus as described by him, they would very quickly lose their energy and fall in to the nucleus and the atom would collapse. Note: Electron moving in circular path gains acceleration and radiate energy and at last dash the nucleus.

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Explain the effect of antibiotic penicillin on bacterial cells

Posted by Sujal Patil 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 4 months ago

Taxonomically, all bacteria are closely related to each other than to viruses and vice versa. This means that many important life processes are similar in the bacteria group but are not shared with the virus group. As a result, drugs that block one of these life processes in one member of the group is likely to be effective against many other members of the group. But the same drug will not work against a microbe belonging to a different group. As an example, let us take antibiotics. They commonly block biochemical pathways important for bacteria. Many bacteria, for example, make a cell-wall to protect them. The antibiotic penicillin blocks the bacterial processes that build the cell wall. As a result, the growing bacteria become unable to make cell-walls, and die easily.

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What can you say about the motion of an object whose distance time graph is a straight line parllel to the time axis

Posted by Aisha Zaffar 7 years, 4 months ago

CBSE > Class 09 > Science

3 answers

Monu Yadav 7 years, 4 months ago

Rest

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Amit Kumar 7 years, 4 months ago

speed of the body is constant

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Prateek Srivastava 7 years, 4 months ago

Uniform motion but confimed it

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On 4 December my physics seminare chapter 12 sound topic will be range of hearing explain this topic

Posted by Naina Patidar 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Prateek Srivastava 7 years, 4 months ago

There are two range that humsn can hear: Infrasonic Sound (0 - 20) hertz Ultrasonic Sound (20 - 2000) hertz

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How to remember postulates of Daltons atomic theory!

Posted by Pranav Lonaree 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Pintu Kumar 7 years, 4 months ago

Sdf

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When is work done 0

Posted by Aastha Bansal 7 years, 4 months ago

CBSE > Class 09 > Science

3 answers

Vijayalakshmi J 7 years, 4 months ago

When the angle is 90° we say the work done is zero. Work done =F s cos θ Where θ is the angle between force and displacement. Where cos 90°=0, so the work done will be zero. Example: A man carry the basket in hand and walk, here force is applied by the hand to carry the basket and displacement is the distance the man travel.

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Nikhil Kumar 7 years, 4 months ago

When. Make angle 90,

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Prateek Srivastava 7 years, 4 months ago

When it is perpendicular or on 90 degree

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what is an molar mass

Posted by Dheeraj Garg 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Prateek Srivastava 7 years, 4 months ago

The molar mass is that which represent the mass of 1 mole of atoms of that substance

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What is atomic number, atomic mass??

Posted by Shravani Aher 7 years, 4 months ago

CBSE > Class 09 > Science

3 answers

Akash Tadwal 7 years, 4 months ago

First atomic number is the defined as the number of protons present number of protons present in nucleus of an atom

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Ansh Khandelwal 7 years, 4 months ago

Atomic mass. the mass of an atom of a particular chemical substance

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Ansh Khandelwal 7 years, 4 months ago

Atomic no. the number of protons that a chemical element has in its centre (nucleus)

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if in nails dead cells are present then how can they grow

Posted by Sangita???? Ankita 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 4 months ago

Nails and hair are essentially made up of a tough protective protein called keratin. While the hair grows in a hair follicle, nails grow from the matrix (the base of the nail bed). Both the hair follicle and the nail matrix are made of epithelial cells and will continue to grow as long as they receive nutrition and remain healthy. As the epithelial cells within the follicle and matrix multiply, the older cells are pushed out, upwards through your skin. They die and harden, thus turning into hair or nails. This process, called keratinisation, makes your hair and nails grow.

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How gas can be liquified

Posted by Ajay Kumar Naik 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Ajay Kumar Naik 7 years, 4 months ago

By applying pressure and decreasing temperature gas can be liquified.

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What are limitations of Thomson's model

Posted by A B 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 4 months ago

According to J.J. Thomson’s model of an atom, an atom consists of a positively charged sphere with electrons embedded in it. However, it was later found that the positively charged particles reside at the centre of the atom called the nucleus, and the electrons revolve around the nucleus.

(a) It could not explain the result of the scattering experiment performed by Rutherford.
(b) It did not have any experimental evidence in its support.

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W what is acceleration motion

Posted by Akash Tadwal 7 years, 4 months ago

CBSE > Class 09 > Science

3 answers

Deba Mardi 7 years, 4 months ago

It is defined as rate of change of velocity with respect to time

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Yogita Ingle 7 years, 4 months ago

The rate of change of velocity is known as acceleration.
It's SI unit is m\sec² .
acceleration = final velocity - initial velocity' time taken

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Tanaya Jadhav☺️ 7 years, 4 months ago

The rate of change of Velocity of an object with respect time

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What are the different states in which water is found during the water cycle

Posted by Devadharshini Karthikeyan 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 4 months ago

Water can be seen in water cycle in its all three different states, These are:
(i) Gaseous State It occurs in the form of water vapour. It evaporates from the surface of water bodies and mixes with air.
(ii) Liquid State Water vapour condense high up in the atmosphere. It falls on the Earth in the form of rain.
(iii) Solid State It is formed by the freezing of liquid droplets in the upper layer of atmosphere. These droplets fall on the Earth in the form of snow, hail or sleet.

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Any five diseases caused by worms

Posted by Sujal Chauhan 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Nandana Muthu 7 years, 4 months ago

Ascariasis Elephantiasis

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What is molar mass of oxygen molecule?

Posted by Aman Yadav 7 years, 4 months ago

CBSE > Class 09 > Science

6 answers

Akash Tadwal 7 years, 4 months ago

16u

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Nikhil Kumar 7 years, 4 months ago

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Tanaya Jadhav☺️ 7 years, 4 months ago

16g/mol

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Akash Tadwal 7 years, 4 months ago

16 u

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Devadharshini Karthikeyan 7 years, 4 months ago

16g if it is O2 then it would be 32g

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Priya Rawat 7 years, 4 months ago

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Difference between canal rays and cathode rays

Posted by Lavamsh Kumar 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 4 months ago

Cathode Rays

* These consist of negatively charged particles called electrons.
* The mass of negatively charged particles does not depend upon the nature of gas taken in the discharge tube.

Canal Rays
* Canal rays is the other name of anode rays which consist of positively charged particles.
* The mass of the positive particles depend upon the nature of gas taken in the discharge tube.

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Define protista

Posted by Avnish Tariyal 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Akash Tadwal 7 years, 4 months ago

Protista is the whittaker classification II Kingdoms and chaterstctics are first this organism are Eukaryotic and unicellular organism second the mode of nutrition Ayan autotrophic or heterotrophic the locomotion is flagella

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What is purpose of making electric bell

Posted by Abhijith Pillai 7 years, 4 months ago

CBSE > Class 09 > Science

0 answers

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Can you object have momentum even if its mechanical energy is zero? Explain .

Posted by Shivansh Handa 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 4 months ago

Yes i can explain this theoritically as
Let a body has both P.E and K.E & P.E = - K.E . then totol mechanical energy =K.E +P.E =0
But momentum is there as body is having some velocity in this case
But i am not sure if it is practically possible or not as there is no such example striking me right now.

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Meaning of plasmolysis

Posted by Unnati Rangwani 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Naina Patidar 7 years, 4 months ago

When a living plant cell loses water through osmosis there is shrinking or constraction of the contents of the cell away from the cell wall this phenomenon is known as plasmolyis.

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what is s,p,d,f in chemstry

Posted by Sangita???? Ankita 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Arpita Singh 7 years, 4 months ago

it is used to find out the valency of any element the value of s= 2 p=4 d=10 f=14

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plz anyone explain me mole concept

Posted by Sangita???? Ankita 7 years, 4 months ago

CBSE > Class 09 > Science

3 answers

Nickson S 7 years, 4 months ago

No. of moles = mass of the substance /molecular mass(in grams)

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Arpita Singh 7 years, 4 months ago

yes offcourse

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Het Patel 7 years, 4 months ago

It is a very big concept. So you can search on google for it or popular videos on it . Try it ,it is the best

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What is atom and moleco

Posted by Himanshi Rani 7 years, 4 months ago

CBSE > Class 09 > Science

3 answers

Akash Tadwal 7 years, 4 months ago

An atom is the smallest particle of an element that cannot be usually exist independently and retain all the chemical properties

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Yogita Ingle 7 years, 4 months ago

Atoms are the smallest particles of an element which can take reaction. Atomic radii of hydrogen atom = 1 × 10^–10 m.

<div>Molecule</div> <div> It is the smallest particle of an eleme4It- or a dicompound which can wxist independently.</div> <div> • Molecules of an element constitutes same type of atoms. 1.w</div> <div> • Molecules may be monoatomic, di-atomic or polyatomic. IT .</div> <div> • Molecules of compounds join together in definite proportion and constitutes different type of atoms.</div>

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Sneha Singh 7 years, 4 months ago

1 The smallest particle of element is calld atom . 2 Two or more atom chemically conbined together to a natural group formed molecule

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Write five importance of food

Posted by J K 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Priya Rawat 7 years, 4 months ago

Food is required us for survive. From food we get energy and energy is required us for doing any type of work.at last food is nessecity fir any living organism.

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What is an electrol role

Posted by Ashif Khan 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 4 months ago

It is a list which carries the names of the persons who are eligible to vote.
It is important because a voter can caste his/her vote if his/her name is in the voter’s list.

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On which galaxy have planets except milkyway galaxy

Posted by Harshmeen Simgh Gill 7 years, 4 months ago

CBSE > Class 09 > Science