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Name the physical quantity

Posted by Arpit Prajapati 7 years, 5 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

What is meant by metrology

Posted by Gajanan. Wankhade. 7 years, 5 months ago

CBSE > Class 09 > Science

3 answers

Shikhar Pandey 7 years, 5 months ago

Science of weights and measures, determination of conformance to specification or technical requirements, and development of standards. Not to be confused with Meteorology, the science of weather phenomenon.

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Yogita Ingle 7 years, 5 months ago

Metrology is the science of measurment . It establishes a common understanding of units, crucial in linking human activities. Metrology is divided into three basic overlapping activities. The first being the definition of units of measurement, second the realisation of these units of measurement in practice, and last traceability, which is linking measurements made in practice to the reference standards.

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Gajanan. Wankhade. 7 years, 5 months ago

Difine metrology

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Endoplasmic reticulum define

Posted by Ranjan Raj 7 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Yogita Ingle 7 years, 5 months ago

The endoplasmic reticulum (ER) is a large network of membrane-bound tubes and sheets. It looks like long tubules or round. There are two types of ER– rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER). RER looks rough under a microscope because it has particles called ribosomes attached to its surface. The ribosomes, which are present in all active cells, are the sites of protein manufacture. The manufactured proteins are then sent to various places in the cell depending on need, using the ER. The SER helps in the manufacture of fat molecules, or lipids, important for cell function.

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Vaibhav Singhania 7 years, 5 months ago

it is membrane network which is found near to nucles

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Thank you for so much

Posted by Mayank Bisht Bisht 7 years, 5 months ago

CBSE > Class 09 > Science

0 answers

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What is formal charge?

Posted by Nityanand Priyadarshi 7 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Yogita Ingle 7 years, 5 months ago

The formal charge over an atom of a polyatomic molecule or ion is the difference between the valence electron of that atom in the elemental state and the number of electrons assigned to that atom in Lewis structure.

Mathematically, it can be expressed by following formula:

F.C. = [Total no. of valence e^– in free state] – [total no. of e^– assigned in Lewis structure]
F.C. = [Total no. of valence e^– in free state] – [total no. of non-bonding pair e^– (lone pair)] – 1/2 [total no. of bonding e^–]

The factor of ½ is attached to the no. of bonding e^– because bonding e^–is shared between two atoms.

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Dheeraj Upraity 7 years, 5 months ago

Patanahi

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What is the formula of area of triangle

Posted by Nagesh Keshri 7 years, 5 months ago

CBSE > Class 09 > Science

4 answers

Soupati Bhanuja 7 years, 5 months ago

General formula 1/2*base*height As per herons formula √s(s-a)(s-b)(s-c)

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Akshat Burnwal 7 years, 5 months ago

The area of triangle is as follows- Let,altitude or height be h And,base be b Then the area=1/2*b*h

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Yash Ghatiya 7 years, 5 months ago

1/2×b×h

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Nagesh Keshri 7 years, 5 months ago

1/2×b×h

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An object weight 25kg on surface of earth what will be the weight on moon and on the earth

Posted by Deepanshi Joshi 7 years, 5 months ago

CBSE > Class 09 > Science

3 answers

Kunal Nawariya 7 years, 5 months ago

=1/6*25=4.1kg approximately

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Kunal Nawariya 7 years, 5 months ago

Mass of object on earth =25 kg Mass of object on moon = 1/6*weight of object on earth

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Shruti Jaiswal 7 years, 5 months ago

Mass of object =25kg We= m.ge =25*9.8 =245 N Wm =m.gm =25*9.8/6 or 245/6 =40.83N

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If a ringing bicycle bell is held tightly by hand, it stops producing sound. Why ?

Posted by Vayu Raj 7 years, 5 months ago

CBSE > Class 09 > Science

0 answers

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Chicken pox doesnt ocuur again because our body is immune against it but why do we catch cold and fever again and again

Posted by Esha Kani 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Shruti Jaiswal 7 years, 5 months ago

It is because chickenpox is caused by a specific virus name Varicella Zoster Virus and when we affect from this then our body prepare itself to fight from it but cold and fever can be caused by any of different of hundreds of virus and for which our body hasn't prepared itself.

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How to find valency number

Posted by Deepak Krishna Kumar 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Harsh Dagar 7 years, 5 months ago

We need to complete octate(8 electrons in outer orbit) of each atom to make it ion(except first five elements they need to completed duplate).Atom can release or gain only 3 electrons.e.g - magnesium(mg) whose atomic no.=12 2nd 1st and 2nd orbit is complete 3rd has just two atoms so it needs to release 2 electrons so it's valency is 2plus

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ANSWER

A mass of 5kg is lifted for 2m above the ground. 1) calculate the work done by the lift. 2) calculate the work done by the gravitational force.

Posted by Jeet Kumar Nayak 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

K.Radha Phanitha 7 years, 5 months ago

Work done =Force×displacement Force is mg W=5×10×2 =100J Work done by gravitational force is -100J. As beacause gravitatiin and work done are opposite in direction

3Thank You

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What is the meaning of plasmid

Posted by Aditya D 7 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Shikhar Pandey 7 years, 5 months ago

According to me plasmid is a small DNA molecule.

1Thank You

Aditya D 7 years, 5 months ago

Plasmid is the additional chromosome preseent in the some of the bacteria cells

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What is dicusion

Posted by Patel Raj 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Utkarsh Raj 7 years, 5 months ago

Discussing something in a group

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What is sonar tecnique?

Posted by Biswa Ranjan Bagarty 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Shikhar Pandey 7 years, 5 months ago

Sonar is technique that uses sound propagation to navigate

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An electric heater is rated 1500w how much energy does it used in 10 hours?

Posted by Khushi Bhadoriya 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Shikhar Pandey 7 years, 5 months ago

Given: Power=1500W=1500/1000=1.5kW time=t=10hours. Energy=Power x t =1.5 X 10 =15kWh Hence , the energy consumed by the heater in 10h is 15kwH

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What is chrophylll

Posted by Shakir Wani 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Shakir Wani 7 years, 5 months ago

The green pigment which is present in leaves and this pigment prepare glucose in leaves

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ANSWER

What does tetra stands for ? Think , it is very easy basic concept

Posted by Rahul Dankhar 7 years, 5 months ago

CBSE > Class 09 > Science

3 answers

Akanksha Gavande 7 years, 5 months ago

It stands as 4 atoms

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Aditya D 7 years, 5 months ago

Tetra stands for more than 3 atoms of an element

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Utkarsh Raj 7 years, 5 months ago

Tetra pack

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Which particle is fastet than the speed of light and who discovered it ?? YOU SHOULD KNOW THIS?

Posted by Amidhi Jain 7 years, 5 months ago

CBSE > Class 09 > Science

3 answers

Shakir Wani 7 years, 5 months ago

Feredick reines discovered neutrino

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Shakir Wani 7 years, 5 months ago

Who discovered it

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Rahul Dankhar 7 years, 5 months ago

Neutrino

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S. I unit of the density

Posted by Robins Raj 7 years, 5 months ago

CBSE > Class 09 > Science

5 answers

Shikhar Pandey 7 years, 5 months ago

SI- kg/m3 CGS- g/cm3

1Thank You

Biswa Ranjan Bagarty 7 years, 5 months ago

Kg/m3

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Saurabh Kumar 7 years, 5 months ago

Kg/m3

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Vidhi Nagar 7 years, 5 months ago

Kg/m3

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Rahul Dankhar 7 years, 5 months ago

kg/m3

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What is the diffrence between lnfectious and non-infectious

Posted by Kriti ?? 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 5 months ago

INFECTIOUS DISEASES	NON-INFECTIOUS DISEASES
1. Caused due to attack of pathogens	1. Caused by factors other than pathogens
2. Caused due to extrinsic factors	2. Caused due to intrinsic factors
3. Transmitted from one person to another	3. Do not get transmitted from one person to another
4. Transmission of diseases occurs through direct contact or some medium (air, water, vectors)	4. Transmission in case of hereditary diseases is from parent to offspring
5. Community hygiene can reduce the occurrence of these diseases	5. Community hygiene is ineffective in reducing the occurrence of these diseases
E.g. Cholera, Malaria	E.g. Diabetes, Goitre

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ANSWER

Nnhgcc

Posted by Ramala Rai 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Vinay Attu 7 years, 5 months ago

Nnhgcc

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What is a pulsar or neutron star....??

Posted by Yash Sharma 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Shikhar Pandey 7 years, 5 months ago

According to me it is a invisible star that send fast regular radio signals.

1Thank You

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What's lichen

Posted by Shirish Pareek 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Shikhar Pandey 7 years, 5 months ago

It is a fungus and algae

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What does the displacement time graph show?

Posted by Bhuva Dev 7 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Miss Angel Barsha 7 years, 5 months ago

It shows velocity

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Yash Sharma 7 years, 5 months ago

Velocity

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What is the deficiency of vitamin a

Posted by Karthik Chand 7 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Miss Angel Barsha 7 years, 5 months ago

It's night blindness

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Yash Sharma 7 years, 5 months ago

Night blindness???

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A bullet is fired normally on wooden plank. If the bullet loses 25% of its momentum in penetrating a thickness of 3.5cm find the total penetrating deoth

Posted by Ekta Jain 5 years, 11 months ago

CBSE > Class 09 > Science

0 answers

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How many bone in our body

Posted by Bhavesh Gurjar 7 years, 5 months ago

CBSE > Class 09 > Science

5 answers

Sudeepti Sharma 7 years, 5 months ago

No there is 300 born in a new born baby and 206 in an adult

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Rahul Lotan 7 years, 5 months ago

206 in adults

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Yash Sharma 7 years, 5 months ago

WRONG........There are actually 305 bones in an average new born babies and 206 in adults....???

2Thank You

Shikhar Boudh 7 years, 5 months ago

Right

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Anuj Doshi 7 years, 5 months ago

270 in birth and 206 in adult

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What are xerophytes

Posted by Humanjit Rabha 7 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Yogita Ingle 7 years, 5 months ago

These plants grow in dry conditions where water is limited. In dry regions all plants not confined to the sides of streams or lakes are considered xerophytes whereas in the regions of high rainfall, xerophytes would likely be represented only by some shallow-rooted plants in light sandy soils, by the vegetation on dry hill-tops and the cryptogamic flora of lichens, algae and mosses.

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Anuj Doshi 7 years, 5 months ago

A plant which needs very little water

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What is the recruitment of cells to an infected part by the active immune system called

Posted by Kunche Charishma 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Anuj Doshi 7 years, 5 months ago

Immunity

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Type of axexual reproduction

Posted by Abhinav Kshatriya 5 years, 11 months ago

CBSE > Class 09 > Science

2 answers

Yogita Ingle 7 years, 5 months ago

Fission: In the process of fission a unicellular organism split to form two or more new organism.
Budding : In budding a small part of a body of parent organism grows out as a bud which then detaches and become a new organism.
For Example: Hydra, yeast reproduce by budding.
Spore formation: In spare formation, the parent plant produces 100 of microscopic reproductive units called “spores” with in the spore case. When the spore case burst, then the spores spread into air. When these air borne spores land on food or soil, under favorable condition they germinate and produce new plants for example: Most of the fungi such as Rhizopus ( bread mould) ,mucor, bacteria, non-flowering plants, ferns and mosses.
Regeneration: The process of getting back off full organism from its body part is called regeneration. For example simple animals like Hydra and Planaria show regeneration.
Fragmentation: The breaking up of body of simple multicellular organism into two or more fragments or maturing, each of which subsequently grows to form a new complete organism is known as fragmentation.
Vegetative Propagation: In vegetative propagation new plants are obtain from the parts of old plants (stem, leaves, or root) without the help of any reproductive organ.