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What do you mean by biodiversity?

Posted by Ashawani Kumar 7 years, 5 months ago

1 answers

Anuj Doshi 7 years, 5 months ago

Biodiversity is a compound word derived from biological diversity Means the variability among living organism from all source included interalia terrestrial marine and equatic ecosystems.

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What is blue green algae

Posted by Deba Mardi 7 years, 5 months ago

CBSE > Class 09 > Science

3 answers

Anuj Doshi 7 years, 5 months ago

Blue green algae generally grow in lakes,ponds, and slow moving streams when the water is a warm and enriched with nutrients like phosphorus OR nitrogen..

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Yash Pratap Singh 7 years, 5 months ago

another term for cyanobacteria ( Cyanobacteria

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Haardik Chaudhary 7 years, 5 months ago

Cynobacteria is modern name of blue green algae It is used for nitrogen fixation

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What is an epidemic disease?

Posted by Shubham Kumar 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Yash Pratap Singh 7 years, 5 months ago

n epidemic is the rapid spread of infectious disease to a large number of people in a given population within a short period of time, usually two weeks or less. For example, in meningococcal infections, an attack rate in excess of 15 cases per 100,000 people for two consecutive weeks is considered an epidemic.

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What is sexual reproduction

Posted by Aditya Singh 7 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Rahul Sharma 7 years, 5 months ago

A type of reproduction in which an organisms produces another organisms similar to itself due to fission of male and female *** organ is called sexual reproduction.

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Deba Mardi 7 years, 5 months ago

Fusion of male and female Gemit

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Homo genous

Posted by Aditya Chauhan 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 5 months ago

Mixtures which have uniform composition throughout are called Homogeneous Mixture. For example – mixture of salt and water, mixture of sugar and water, air, lemonade, soda water, etc.

Mixture of salt in water is an example of homogeneous mixture. In this mixture, the boundary of salt and water cannot be differentiated. When a ray of light is passed through the mixture of salt and water, the path of light is not seen.

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What is difference between inertia and newton 's first law of motion.

Posted by Sia Joy 7 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Ananya Jaiswal 7 years, 5 months ago

According to Newton's first law of motion if a body is in rest will remain at rest and if a body is in motion will remain in motion until or unless an external force is not applied. Inertia is a property of body by which a particular body resists to change its state of motion

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Rahul Kumar 7 years, 5 months ago

newton's 1st law describes that any body in rest it tends to in rest and any body in motion it tends to in motion. But inertia is the property of tendecy to being continued in that state.

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What is atomic number of carbon

Posted by Gaurav Sehgal 7 years, 5 months ago

CBSE > Class 09 > Science

5 answers

Indian Pro 7 years, 5 months ago

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Nandini Agarwal 7 years, 5 months ago

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Ananya Jaiswal 7 years, 5 months ago

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Madni Memon 7 years, 5 months ago

Atomic no. Is 6 and molar mass is 12

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Suwathi B 7 years, 5 months ago

Simple,6

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What is the derivation of work and energy

Posted by Khushi Singh 7 years, 5 months ago

CBSE > Class 09 > Science

0 answers

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A solid object of mass 250kg imersed in a liquid calculate the buoyant force

Posted by Manish Gupta 7 years, 5 months ago

CBSE > Class 09 > Science

0 answers

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When did you observe that the air inside seemed to become‘foggy’?

Posted by Abisek Chhetri Abisek Chhetri 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Dinesh Patel 5 years, 1 month ago

idk?

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What is cos theta????

Posted by Gurnoor Kaur 7 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Anoushka Giri 7 years, 5 months ago

Cos theta is basically a trigonometry concept ..where theta is the angle formed. EG- if a force is applied to an object at 90 degrees then the work done will be 0. Formula is :- W=F×S×Cos theta

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Anoushka Giri 7 years, 5 months ago

Hi Gurnoor Kaur

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An element form compound MH3 when react with hydrogen write valency of hydrogen

Posted by Yahya Altaf 7 years, 5 months ago

CBSE > Class 09 > Science

0 answers

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State any four differences between the positive , negative and zero work done? (Physics,work and energy)

Posted by Hartejpal Dhillon 4 years, 9 months ago

CBSE > Class 09 > Science

1 answers

Sia ? 4 years, 9 months ago

Positive work - When force and displacement are in the same direction, the work performed on an object is said to be positive work.
Example: When a body moves on the horizontal surface, force and displacement act in the forward path. The work is done in this case known as Positive work.

Negative work - Negative work is performed if the displacement is opposite to the direction of the Force applied.
Example: Work was done the gravity on a rocket going perpendicular upwards.

Zero work - When force and displacement are perpendicular to each other, or when force or displacement is zero.
Example: When we hold an object and walk, the force acts in a downward direction whereas displacement acts in the forward direction.

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State law of conservation of momentum and newton ,s second law.express mathematically

Posted by Sweety Muskan 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 5 months ago

According to law of conservation of momentum : When two or more bodies acts upon each other their total momentum remains constant provided no external forces are acting.

Newton's second Law of Motion states that The rate of change of momentum is directly proportional to the force applied in the direction of force.

For example; when acceleration is applied on a moving vehicle, the momentum of the vehicle increases and the increase is in the direction of motion because the force is being applied in the direction of motion. On the other hand, when brake is applied on the moving vehicle, the momentum of the vehicle decreases and the decrease is in the opposite direction of motion because the force is being applied in the opposite direction of motion.

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Absorption of water by plant roots is an example of?

Posted by Prachi Goswami 7 years, 5 months ago

CBSE > Class 09 > Science

3 answers

Miss Angel Barsha 7 years, 5 months ago

It is the example of osmosis

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Ananya Jaiswal 7 years, 5 months ago

Osmosis

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Vivek Kumar 7 years, 5 months ago

Osmosis

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What is the state of motion of a body

Posted by A. Santosh Kumar 7 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Miss Angel Barsha 7 years, 5 months ago

To rest

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Rushikesh Gaikwad 5 years, 11 months ago

Rest

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Why the value of 'g' on earth is maximum at the poles and minimum at the equator

Posted by Simran Sarao 7 years, 5 months ago

CBSE > Class 09 > Science

3 answers

Miss Angel Barsha 7 years, 5 months ago

9.8MS2

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Yogita Ingle 7 years, 5 months ago

Acceleration due to gravity on the surface of earth g = GM/r², where r is the radius of the earth, M the mass of the earth and G the universal gravitational constant.
In the above expression for g, G and M are constant. But r varies due to the shape of the earth. We know that the shape of the earth is not a perfect sphere. It is flattened at the poles and bulged at the equator. So the polar radius is smaller than the equitorial radius. Hence g is slightly more at the poles than at the equator.
Thus the value of g on earth is maximum at poles and decreases as we go from poles to the equator and is minimum at the equator. also g decreses as we increase or decrease the distance of a body from the centre of the earth.
Also the value of g decreases as we go above the sea level and again decreses deep iside the earth.

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Hartejpal Dhillon 7 years, 5 months ago

At poles the value of g is greater i.e 10 than its value at equater i.e 9.8 .

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Difference between infection and disease

Posted by Vinod Vishnoi 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Anonymous Nameless 7 years, 5 months ago

difference of 2 letters in case of spelling

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Plz explain the cathode and anode rays

Posted by Shriti Gangil 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

G B 7 years, 5 months ago

Cathode ray travel from cathode to anode , negatively charged ,made up of electons , travel in discharge tube with extremly high voltage 10000 and extremly low pressure 0.01 and does not depend on nature of gas present in discharge tube Anode rays trave from anode to cathode,positively charged,made up of protons tavel in discharge tube with extremly high pressure 10000 and extremly low pressure 0.01, depends upon nature of gas present in discharge tube , discovered by E.goldstein , also called canal rays

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Whatsrelative density

Posted by Yug - 7 years, 5 months ago

CBSE > Class 09 > Science