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Numerical related with PE=mgh

Posted by Sweetu Patel 3 years, 6 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

Numerical related with KE= ½ mv2

Posted by Sweetu Patel 3 years, 6 months ago

CBSE > Class 09 > Science

1 answers

Siddhi Goyal 3 years, 6 months ago

search in book

ANSWER

Write the postulates of Rutherford's model of atom

Posted by Pawandeep Kaur 3 years, 6 months ago

CBSE > Class 09 > Science

4 answers

Jiya Yadav 3 years, 6 months ago

Postulates of Rutherford atomic model based on observations and conclusions. Atoms nucleus is surrounded by negatively charged particles called elwectrons. The electrons revolve around the nucleus in a fixed circular path at very high speed. These fixed circular paths were termed as “orbits.”

Aditi Kumari 3 years, 6 months ago

1‐ Most of the atom is empty space.2‐An atom is electrically neutral. This is because the number of protons and electrons in an atom is equal 3‐ An atom consists of a positively charged, dense and very small nucleus containing all the protons and neutrons .Almost the entire mass of an atom is concentrated in the nucleus. 4‐ The nucleus is surrounded by the negatively charged electrons. The electrons are revolving the nucleus in circular path at very high speed. The circular path of the electron are called orbits .

Seema Afroz 3 years, 6 months ago

What is cell

Manyata Joshi 3 years, 6 months ago

Postulates of Rutherford atomic modelbased on observations and conclusions. An atom is composed of positively charged particles. Atoms nucleus is surrounded by negatively charged particles called electrons. The electrons revolve around the nucleus in a fixed circular path at very high speed.

ANSWER

Do true solution, colloidal and suspension pass through filter paper and parchment paper?? What passes through it and what not....?? Matter in our surroundings...class 9... science...

Posted by Drashya Shah 3 years, 6 months ago

CBSE > Class 09 > Science

4 answers

Rishabh Kothari 3 years, 6 months ago

True solutions and colloidal solution passes through filter paper.

Bhoomi Garg 3 years, 6 months ago

Only true solution or solution can only pass through filter paper but suspension does not pass through filter paper

Anurag Shekhar 3 years, 6 months ago

True solutions and colloidal solutions pass through filter paper and suspension does not

Drashya Shah 3 years, 6 months ago

Pl tell its answer....

ANSWER

Difference between blood and lymph

Posted by Pawandeep Kaur 3 years, 6 months ago

CBSE > Class 09 > Science

3 answers

Drashya Shah 3 years, 6 months ago

Hope it help u ????

Drashya Shah 3 years, 6 months ago

LYMPH Lymph carries digested fat and a lot of white blood cells in the plasma.

Drashya Shah 3 years, 6 months ago

BLOOD Blood has a fluid (liquid) matrix called plasma, in which red blood cells (RBCs), white blood cells (WBCs) and platelets are suspended. The plasma contains proteins, salts and hormones. Blood flows and transports gases, digested food, hormones and waste materials to different parts of the body.

ANSWER

What is the physical state of water at 0⁰c

Posted by Mohd Haseeb 3 years, 6 months ago

CBSE > Class 09 > Science

5 answers

Jhanvi Chouhan 3 years, 6 months ago

Solid

Vidushi Chordia 3 years, 6 months ago

Solid

Uplaksh Goel 3 years, 6 months ago

Solid

Shivam Tyagi 3 years, 6 months ago

Ice

Ranjeet Kumar Pandit?? 3 years, 6 months ago

Solid

ANSWER

Chapter 1 of science of 9th class

Posted by Kanika Sharma 3 years, 6 months ago

CBSE > Class 09 > Science

2 answers

Arhaan Mallik 3 years, 6 months ago

Ncert :- Matter in our surrounding

Uplaksh Goel 3 years, 6 months ago

Bio, chemistry or physics?

ANSWER

Define orbit

Posted by Amrit1158C☣️ Sb 3 years, 6 months ago

CBSE > Class 09 > Science

3 answers

Aditi Kumari 3 years, 6 months ago

The circular path of the electron are called orbits.

Drashya Shah 3 years, 6 months ago

Hope it help u ????

Drashya Shah 3 years, 6 months ago

Orbit is a well-defined circular path around the nucleus in which electrons revolve around the nucleus. It is also called a shell. It is denoted by the principal quantum number 'n'. Electrons can jump from one orbit to another by either absorbing energy or releasing energy.

ANSWER

What is the electric confricasion of oxygen

Posted by Anurag Singh Thakur 3 years, 6 months ago

CBSE > Class 09 > Science

4 answers

Atul Kumar 3 years, 6 months ago

Electronic configuration of oxygen means O2 will be 2,6 in K,L because we all know that atomic no.of oxygen is 8 so first of all it will fill the K shell that is 2 and after that it will fill the L Shell that is 6 . But in case of S,P,D,F the electronic configuration will be 1s² 2s² 2p⁴ that is 2+ 2+4 is= 8.

Veera Babu R 3 years, 6 months ago

[He] 2s² 2p⁴

Ananya Singh 3 years, 6 months ago

K orbit me 2electron l me 6

Bharti Rani 3 years, 6 months ago

K L 2 6

ANSWER

Science it 2 mae ch=5,8 ayege

Posted by Pushkar Rawat 3 years, 6 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

How big are atoms ?

Posted by Koina Shiyal 3 years, 6 months ago

CBSE > Class 09 > Science

4 answers

Ashmita Das 3 years, 6 months ago

They are nearly of 1nm

Ranjeet Kumar Pandit?? 3 years, 6 months ago

Atom are smallest among all with which we compare or imagine it.size of atom be 1nm=10^-9m

Toshak Thakre 3 years, 6 months ago

Smaller than these (.)

Koina Shiyal 3 years, 6 months ago

Please help

ANSWER

M difference between h*********

Posted by Koina Shiyal 3 years, 6 months ago

CBSE > Class 09 > Science

2 answers

Sibaram Dalai 3 years, 6 months ago

Nice

Uplaksh Goel 3 years, 6 months ago

h********?

ANSWER

Can a body posses Kenitic Energy with out momentum

Posted by Dev Dubey 3 years, 6 months ago

CBSE > Class 09 > Science

2 answers

Devika K 3 years, 6 months ago

No

Haarish Ahmad 3 years, 6 months ago

No because kenitic enegry is the energy produced due to momentum

ANSWER

Example of Uniformly accelarated motion

Posted by Gayatri Shinde 3 years, 6 months ago

CBSE > Class 09 > Science

2 answers

Aditi Kumari 3 years, 6 months ago

Freely falling body. Bicycle going down the clop of the road Ball rolling down an inclined plane.

Ashmita Das 3 years, 6 months ago

Motion of a body falling freely under the action of gravity

ANSWER

What is electric confugaration

Posted by Anand Kumar 3 years, 6 months ago

CBSE > Class 09 > Science

5 answers

Tanishq Kumar 3 years, 6 months ago

Electronic configuration of an atom is arrangement of electrons from its higher level around the nucleus

Devika Lather 3 years, 6 months ago

Electronic configuration also called electronic structure. The arrangement of electrons in energy level around an atomic nucleus.

Devika Lather 3 years, 6 months ago

Electronic configuration,

Bharti Rani 3 years, 6 months ago

K l m n by bohrs formula

Dev Dubey 3 years, 6 months ago

Valency

ANSWER

What is osmosis? Classify the solutions on the basis of concentration(3marks )

Posted by Sweetu Patel 3 years, 6 months ago

CBSE > Class 09 > Science

3 answers

Saloni Tunwar 3 years, 6 months ago

The process in which the movement of water and any substance through a plasma membrane ,high to low concentration is called osmosis

Rishabh Kothari 3 years, 6 months ago

The passage of water from a region of high concentration to a region of low concentration through a semi-permeable membrane is called osmosis. The classification of solution on the basis of concentration is saturated, unsaturated solution.

Archi Jain 3 years, 6 months ago

Movement of water from a region of higher concentration to lower concentration semi permeable membrane this is called osmosis

ANSWER

Whai is tendal effect?

Posted by Rishi Yadav 3 years, 6 months ago

CBSE > Class 09 > Science

3 answers

Shivam Tyagi 3 years, 6 months ago

The light which is obtained from collid solution is thyndal effect

Dev Dubey 3 years, 6 months ago

Scattering of a beam of light in colloidal solution is called Tyndall effect

Suraj Yadav 3 years, 6 months ago

Tyndall effect, also called Tyndall phenomenon, scattering of a beam of light by a medium containing small suspended particles—e.g., smoke or dust in a room

ANSWER

Define Vaccination... Class 9 ... why do we fall ill...pl tell its answer

Posted by Drashya Shah 3 years, 6 months ago

CBSE > Class 09 > Science

3 answers

Ashmita Das 3 years, 6 months ago

Vaccination is a biologically prepared product which contains typical agents resembling a microorganism that causes diseases, made from weakened or dead forms of the microbes, one of its surface proteins or its toxic

Rishabh Kothari 3 years, 6 months ago

Vaccination is the preparations for the prevention of disease earlier

Rohit Das 3 years, 6 months ago

Vaccination is a preparation that improves immunity to a particular disease. It is a biologically prepared product which contains typical agents resembling a microorganism that causes diseases, made from weakened or dead forms of the microbes, one of its surface proteins or its toxic

ANSWER

Why do meristematic tissue lack vacuoles?

Posted by Rishabh Kothari 3 years, 6 months ago

CBSE > Class 09 > Science

3 answers

Toshak Thakre 3 years, 6 months ago

Because of continuously dividing

Archi Jain 3 years, 6 months ago

Merstimatic tissues lack vacoules due to because they are continuously dividing so, they didn't need for any storage hence we know that function of vacoules is used for storage

Pooja Tyagi 3 years, 6 months ago

°•

ANSWER

Plz tell aome common questions for exam of 9th class

Posted by Sarthak Gartan 3 years, 6 months ago

CBSE > Class 09 > Science

3 answers

Vidushi Chordia 3 years, 6 months ago

Bio

Ranjeet Kumar Pandit?? 3 years, 6 months ago

1.Define diffusion and osmosis 2.why plasma membrane is known as semipermeable membrane 3.what is cell division 4.name two organnels which have own DNA and protons 5.Define acute and chronic disease 6.define the vaccination 7.what is atom 8.define one mole 9.draw the labelled diagram of parenchyma,collenchyma and sclerenchyma 10.differentiate between electron ,proton and neutron 11.explain universal law of gravitation 12.prove:F=G×m1×m2/r^2 13.what is distillation 14.prove kinetic energy 15.differentiate between distance and displacement 16.differentiate between mass and weight 17.define balanced and unbalanced force 18.what is energy 19.what is acid rain 20.define nervous tissue 21.what is global warming 22.define law of constant proportion 23.what was Dalton atomic theory 24.prove law of conservation of mass 25.by which process we can separate two immiscible liquid 26.define colloidal solution 27.difference between mixture and compound 28.plasma membrane made up of which things 29.cell wall made up of which things 30.give characteristics of bone 31.what is voluntary muscles 32.explain free fall 33.what is buoyant force 34.define infectious diseases 35.who discovered the vaccination and how 36.how ozone layer useful for human beings 37.define third law of motion 38.what is inertia 39.define effect of force 40.differentiate xylem and phloem

Suraj Yadav 3 years, 6 months ago

Which subject

ANSWER

Explain with example the different means by which infectious diesease can spread??

Posted by Prashant Rai 3 years, 6 months ago

CBSE > Class 09 > Science

1 answers

Bhargavi Kulkarni 3 years, 6 months ago

for example communicable disease spread from infected person to healthy through air , water , food or by physical contact or such disease causing microbes can spread through air this occur through the little droplets thrown out by infected person who sneezes or coughs example = common cold , pneumonia , tuberculosis

ANSWER

ANY BODY CAN SEND ME SCIENCE BLUE PRINT 2021 WITH DELETED SYLLABUS

Posted by Gigi8 Jvigigogogo 3 years, 6 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

Why are the cells of meristematic tissues lack of vacuoles

Posted by Mohit Kumar 3 years, 6 months ago

CBSE > Class 09 > Science

1 answers

Shiven Yadav 3 years, 6 months ago

Because their only function is to increase in their organs a d body parts

ANSWER

A 3000kg truck moving a speed of 90m/s stops after covering some distance the force applied by brakes is 27000N compute the distance covered and work done by the force.

Posted by Minu Dalei 3 years, 6 months ago

CBSE > Class 09 > Science

2 answers

Rishabh Kothari 3 years, 6 months ago

Can anyone write the steps for this sum?

Pravesh Giri 3 years, 6 months ago

7.29 E9 is the answer .

ANSWER

1) Force person jointly lift a 250kg box to a height of 1m and hold it i)Calculate the work done by the person in lifting the box? ii) How much work is done for just holding the box ?

Posted by Minu Dalei 3 years, 6 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

Differentiate between mass no. and atomic number.

Posted by Sweetu Patel 3 years, 6 months ago

CBSE > Class 09 > Science

1 answers

Vidharshana Yathra Prakkash 3 years, 6 months ago

MASS NO: THE SUM OF PROTOAN AND NEUTRON ATOMIC NO:NO OF ELECTRONS PRESENT IN A NUCLEUS

ANSWER

Force person jointly a 250kg box to a height

Posted by Minu Dalei 3 years, 6 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

Force person jointly lift a 250kg box to a height of 1m and hold it

Posted by Minu Dalei 3 years, 6 months ago

CBSE > Class 09 > Science

1 answers

Minu Dalei 3 years, 6 months ago

Calculate the work done by the person in lifting the box

ANSWER

What is bohar modal of an atom

Posted by Amrit1158C☣️ Sb 3 years, 6 months ago

CBSE > Class 09 > Science

3 answers

Harpreet Singh 3 years, 6 months ago

The electron cloud model is currently the most sophisticated and widely accepted model of the atom. It retains the concept of the nucleus from Bohr and Rutherford's models, but introduces a different definition of the motion of electrons around the nucleus.

Harpreet Singh 3 years, 6 months ago

1. How do electrons move in Bohr’s model? Ans: The theory notes that electrons in atoms travel around a central nucleus in circular orbits and can only orbit stably at a distinct set of distances from the nucleus in certain fixed circular orbits. Such orbits are related to certain energies and are also referred to as energy shells or energy levels. 2. How did Bohr discover electrons? Ans: Bohr was the first to discover that electrons move around the nucleus in different orbits and that an element’s properties are determined by the number of electrons in the outer orbit. 3. Did Bohr’s model have neutrons? Ans: The nucleus in the atom’s Bohr model holds most of the atom’s mass in its protons and neutrons. The negatively charged electrons, which contribute little in terms of mass, but are electrically equivalent to the protons in the nucleus, orbit the positively charged core. 4. How did Sommerfeld modify Bohr’s theory? Ans: Many modifications have been introduced to the Bohr model, most notably the Sommerfeld model or Bohr – Sommerfeld model, which suggested that electrons move around a nucleus in elliptical orbits rather than circular orbits of the Bohr model. The Bohr – Sommerfeld system was essentially incoherent, contributing to many paradoxes. 5. Who discovered electrons? Ans: J. J. Thomson in 1897 discovered Electron when he was studying the properties of the cathode ray.

Harpreet Singh 3 years, 6 months ago

Bohr model of the atom was proposed by Neil Bohr in 1915. It came into existence with the modification of Rutherford’s model of an atom. Rutherford’s model introduced the nuclear model of an atom, in which he explained that a nucleus (positively charged) is surrounded by negatively charged electrons. Bohr modified this atomic structure model by explaining that electrons move in fixed orbitals (shells) and not anywhere in between and he also explained that each orbit (shell) has a fixed energy level. Rutherford basically explained the nucleus of an atom and Bohr modified that model into electrons and their energy levels. Bohr’s model consists of a small nucleus (positively charged) surrounded by negative electrons moving around the nucleus in orbits. Bohr found that an electron located away from the nucleus has more energy, and electrons close to the nucleus have less energy. Postulates of Bohr’s Model of an Atom In an atom, electrons (negatively charged) revolve around the positively charged nucleus in a definite circular path called orbits or shells. Each orbit or shell has a fixed energy and these circular orbits are known as orbital shells. The energy levels are represented by an integer (n=1, 2, 3…) known as the quantum number. This range of quantum number starts from nucleus side with n=1 having the lowest energy level. The orbits n=1, 2, 3, 4… are assigned as K, L, M, N…. shells and when an electron attains the lowest energy level, it is said to be in the ground state. The electrons in an atom move from a lower energy level to a higher energy level by gaining the required energy and an electron moves from a higher energy level to lower energy level by losing energy. Limitations of Bohr’s Model of an Atom Bohr’s model of an atom failed to explain the Zeeman Effect (effect of magnetic field on the spectra of atoms). It also failed to explain the Stark effect (effect of electric field on the spectra of atoms). It violates the Heisenberg Uncertainty Principle. It could not explain the spectra obtained from larger atoms.

ANSWER

Definition of motion

Posted by Gautam Kumar Yadav 3 years, 6 months ago

CBSE > Class 09 > Science

3 answers

Aditi Kumari 3 years, 6 months ago

A body is said to he in motion (or moving)when its position changes continuously with respect to a stationary object.

Ved Bhilware 3 years, 6 months ago

Motion, in physics, change with time of the position or orientation of a body. Motion along a line or a curve is called translation. ... In both cases all points in the body have the same velocity (directed speed) and the same acceleration (time rate of change of velocity).

Akshiii ?? 3 years, 6 months ago

Anything which is in state of moving ,is said to be in motion.~ Hope it helps ?

ANSWER

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