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A fast moving cricket ball has a large momentum. In stopping or catching this ball, its momentum has reduced to be zero. Now, when a cricket player moves back his hands on catching the fast ball, then the time taken to reduce the momentum of ball to zero is increased. Due to more time taken to stop the ball, the rate of change of momentum of ball is decreased and hence a small force is exerted on the hands of player. So, the hands of player do not get hurt.

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Ankit Ambasta 7 years, 2 months ago

A cricket player pulls his hand while catching a ball so that the natural acceleration on ball will not affect or hurt the player.

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can anyone know the density of air

Posted by Sangita???? Ankita 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Gaurav Seth 7 years, 2 months ago

Air density, like air pressure, decreases with increasing altitude. It also changes with variation in temperature or humidity. At sea level and at 15 °C, air has a density of approximately 1.225 kg/m3

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Calculate the (a) no.of moles in 12g of iron [At.mass=564]

Posted by Arun Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Goutam Dalal 7 years, 2 months ago

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Write formula of H&s

Posted by Ishan Vashishtha 7 years, 2 months ago

CBSE > Class 09 > Science

0 answers

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What universal law of gravitation

Posted by Prabhash Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Ankit Ambasta 7 years, 2 months ago

The universal law of gravitation states that every object attract each other with a force that is directly proportional to product of their masses and square of distance b/w them.

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What causes water pollution

Posted by Jassim Jaleel 7 years, 2 months ago

CBSE > Class 09 > Science

3 answers

Ankit Ambasta 7 years, 2 months ago

-Excess use of chemical fertilizers. Such as NPK. -Waste generated by big factories. -Supplying untreated water direct to rivers. -Disturbance in water cycle .

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Saijal Singh 7 years, 2 months ago

Humans are the main cause of water pollution, which is triggered in many ways: by the dumping of industrial waste; due to temperature rise, that cause the alteration of water byhtthe oxygen in its composition; Or due to deforestation, which causes sediments and bacteria to appear under the soil and therefore contaminate groundwater. In the same way, the pesticides used in agricultural fields filter through underground channels and reach the consumption networks; And also as a result of accidental spillage of oil. What are the effects of water pollution? What are the main consequences of water pollution? Firstly, the disappearance of biodiversity and aquatic ecosystems. Also, humans are harmed by the alteration in the food chain and by contracting illnesses when drinking or using contaminated water. As you can see, water pollution has a great impact in the environment. For all this, we must ensure water availability, its sustainable management and sanitation for all, as reflected in the sixth of the Sustainable Development Goals adopted by the United Nations in the 2030 Agenda.

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Saijal Singh 7 years, 2 months ago

Water pollutants ?

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Define rain

Posted by Dhaliwal Empire 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Ankit Ambasta 7 years, 2 months ago

The last stage in watercycle known as rain. Tiny droplets of water falls on earth this phenomenon is known as rain.

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Name two giant molecules.

Posted by Riya Gupta 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Kapil Dev Mishra 7 years, 2 months ago

(polymers are a different kind of large molecule). exist in the same physical state, they are called allotropes. Carbon can exist as fullerenes as well as diamond and graphite.

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What would be acceleration of a body if its velocity- time graph is a line parallel to the time axis?

Posted by Anshu Dubey 7 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Ankit Ambasta 7 years, 2 months ago

The object will be on rest

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Anshu Dubey 7 years, 2 months ago

Uniform acceleration

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Define atmosphere

Posted by Pg Villan 7 years, 2 months ago

CBSE > Class 09 > Science

4 answers

Sayahnika Mishra 7 years, 2 months ago

The blanket of air that surrounds the earth is called atomsphere??

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Avishek Vishwakarma 7 years, 2 months ago

Atmosphere is a type of a blanket which surrounds by many mixtures of gasses

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Shaik Haneef 7 years, 2 months ago

The layer of sky which is fully mixed with many gases mainly nitrogen oxygen and carbon dioxide

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Prem Gill 7 years, 2 months ago

The layer of air in our surrounding is called atmosphere.

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Define amplitude,frequency, pitch and intensity of sound

Posted by Arya Magade 7 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Ajay Jangra 7 years, 2 months ago

The write answer of amplitude is that the distance between two consecutive crest and trough is called amplitude

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Prem Gill 7 years, 2 months ago

Amplitude- The distance between crest and trough is called amplitude of sound. Frequency-No. of times the oscillation done per second is called frequency . Pitch- The property of sound which depends on its frequency is called pitch

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Give two examples of macronutrients?

Posted by Neha Panwar 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Prem Gill 7 years, 2 months ago

Phosphorus and calcium

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The atomic number of phosphorus is

Posted by Purshottam Sharma 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Saijal Singh 7 years, 2 months ago

5Thank You

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Name the class in which the pesudo segment is present

Posted by Roman Dhanush 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Ankit Ambasta 7 years, 2 months ago

Annelida

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Difference between evaporation vaprition

Posted by Aditya Manjhi 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Jatin Vermq 7 years, 2 months ago

Vapourization is the phase of transittion of a substancefrom liquid to vapour Evaporation is a type of vapouriZation that occurs at the surface of a liquid at temperature below the boiling temperature

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Difference bw hapititis a b and c

Posted by Kajal Patel 7 years, 2 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

Where is the gravity zoro

Posted by Manvendra Singh 7 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Yogita Ingle 7 years, 2 months ago

Acceleration due to the earth's gravity is zero at the centre of the Earth because at that point the mass of the earth is equally distributed in all directions, so pulling equally in all directions for a net zero pull.

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Saijal Singh 7 years, 2 months ago

At the center of the earth

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व्हॉट इज मिन बाय soil

Posted by Tejas Narode 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Avishek Vishwakarma 7 years, 2 months ago

Soil in the mixture of many organic substances including the dead remains of plant, animal and many things which we cannot be able to see with our naked eyes.

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Which cropping system can help a farmar to have maximum profit his available agricultural loss

Posted by Aditya Sharma 7 years, 2 months ago

CBSE > Class 09 > Science

3 answers

Shivam Yadav 7 years, 2 months ago

Multiple cropping can help rhe farmer to have a profit in farming

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Yugesh Girade 7 years, 2 months ago

good irrigation and hyv seeds

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Ankit Ambasta 7 years, 2 months ago

Mixed Cropping with artificial irrigation system and HYV seeds

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What does small value of G indicates?

Posted by Ankit Ambasta 7 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Eashani Eashani 7 years, 2 months ago

Universal gravitation constant

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Sayahnika Mishra 7 years, 2 months ago

9.8m/s2

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What is the nature of distance time graph for uniform and non - uniform motion of an object ?

Posted by Rajat Gaur 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 2 months ago

(a) The slope of the distance-time graph for an object in uniform motion is straight line.
(b) The slope of the distance-time graph for an object in non-uniform motion is not a straight line.

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Calculate the number of molecules of sulhpur (S8) produced in 16 gram of solid sulphur

Posted by Ujjwal Sharma 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Shantanu Singh 7 years, 2 months ago

128

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What is kinetic energy derived its formula ?

Posted by Shivam Maheshwari 7 years, 2 months ago

CBSE > Class 09 > Science

3 answers

Shantanu Singh 7 years, 2 months ago

1/2mv^2

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Simran Kaur 7 years, 2 months ago

Yaar pradeeps mai hsi toh derivation dekhoo...its too easy

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Shanu Sharma 7 years, 2 months ago

It is the energy posessed by its motion of its motion

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Chemical formula of sulphur dioxide

Posted by Sudhansu Sekhar Dash 7 years, 2 months ago

CBSE > Class 09 > Science

3 answers

Prem Gill 7 years, 2 months ago

So2

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Ankit Ambasta 7 years, 2 months ago

Energy possed due to motion of objects known as kinetic energy. DERIVATION........ WORK =FOECE*DISPLACEMENT W=F*S......1 F=M*a......2 Fm 3rd equation of motion V"2 —U"2 = 2aS S=V"2—U"2/2a. .......3 Fm. 1,2and3 we get Kinetic energy= 1/2M V"2

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Bhavya Singh 7 years, 2 months ago

SO4

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What is the atomic mass of sulphur

Posted by Jesna T J Jesna T J 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Bhavya Singh 7 years, 2 months ago

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A ball is dropped 2.5 m above the ground a.find the speed with which it reaches the floor. b. the ball now rebounds the speed of ball is decreased by three fourth of its original speed by collision how much the ball is after rebounds

Posted by Prince Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Prince Kumar 5 years, 11 months ago

Answer

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What is a formula unit mass? Explain with an example

Posted by Priyadarsini Hotta 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Priyadarsini Hotta 7 years, 2 months ago

It is the sum of the atomic masses of all atoms present in a formula unit of a compound. Example : formula unit mass of sodium chloride ( NaCl) = 1*23+1*35.5=58.5u

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Electron is also known was earlier time..

Posted by Avishek Vishwakarma 7 years, 2 months ago

CBSE > Class 09 > Science