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Name the term which is used for the following:- 1) the left and right halves of the body have the same design. 2) the animal tissue differentiation from the three embryonic layer.

Posted by Tina Kukreja 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Akanksha Maurya 7 years, 1 month ago

1) bilateral symmetry that is the left and right halves of the body have the same design. 2) triploblastic , that is the three layers of cells differentiated tissue .

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Arsh Pathan 7 years, 1 month ago

1) billaterally symmetrical

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Two organism with cell wall

Posted by Suraj Kumar 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Akanksha Maurya 7 years, 1 month ago

Amoeba

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Tina Kukreja 7 years, 1 month ago

Eukaryotic organism such as algae , fungi amd higher plants

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ANSWER

The acceleration due to gravity near the earth surface is 9.8 metre per second square and the earth radius is 64,00 kilometre from this data calculate the mass of the earth use any Universal constant if required

Posted by ?????? ?? 7 years, 1 month ago

CBSE > Class 09 > Science

0 answers

ANSWER

In the hare tortoise race,the hare ran for 2 minutes at aspeed of 7.5 km per hour slept for 56 minute and again ran for 2 minute at a speed of 7.5 km per hour find average speed of the hare in the race

Posted by ?????? ?? 7 years, 1 month ago

CBSE > Class 09 > Science

0 answers

ANSWER

In the hare tortoise race the hare ran for

Posted by ?????? ?? 7 years, 1 month ago

CBSE > Class 09 > Science

0 answers

ANSWER

what is the SI unit of amplitude?

Posted by Jay Joshi 7 years, 1 month ago

CBSE > Class 09 > Science

3 answers

Huzefa Khan 7 years, 1 month ago

Metre is SI unit of amplitude

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Tina Kukreja 7 years, 1 month ago

SI unit of amplitude:- m

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Sakshi . 7 years, 1 month ago

Normally the symbol A is used to represent the amplitude of a wave. The SI unit of amplitude is the metre (m).

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ANSWER

what is the SI unit of density or pressure

Posted by Jay Joshi 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Tina Kukreja 7 years, 1 month ago

SI unit of density :- kg/m^3 SI unit of pressure :- pascal (pa)

2Thank You

Abhishek The Great Leader 2019 7 years, 1 month ago

The si unit of pressure is pascal

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ANSWER

similarity between cardic muscle or smooth muscle

Posted by Vikash Kumar 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Srishti Agarwal 7 years, 1 month ago

They do not work according to our will.

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Abhishek The Great Leader 2019 7 years, 1 month ago

Cardiac and smooth muscle have smooth structure

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Which two vitamins essential for poultry farming?

Posted by Ankit Raj 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Meghna Thapar 6 years, 1 month ago

Chickens are raised up to 6-7 weeks in the poultry farm. They are fed with vitamin rich supplementary feed for good growth rate and better feed efficiency.

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Describe the working of sonar

Posted by Uzer Saifi 7 years, 1 month ago

CBSE > Class 09 > Science

3 answers

Gaurav Seth 7 years, 1 month ago

The acronym SONAR stands for Sound Navigation and Ranging.

Sonar is a device that uses ultrasonic waves to measure the distance, direction and speed of underwater objects.

Principle: It uses the phenomenon of echoes in determining the sea-depth and locating the presence of under-water objects.

Working:

i) Sonar consists of a transmitter and a detector and is installed in a boat or a ship.

ii) The transmitter produces and transmits strong ultrasonic waves.

iii) These waves travel through the water and after striking the object the beam is reflected from the seabed and is received by an under-water detector which is also mounted on the ship.

iv) The detector converts the ultrasonic waves into electrical signals which are appropriately interpreted.

v) The time interval between transmission and reception of the ultrasonic signal is noted.

The SONAR method is also called echo ranging. This technique is used to determine the depth of the sea and to locate underwater hills, valleys, submarine, icebergs, sunken ship etc.

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Atharv Khandelwal 7 years, 1 month ago

It consists three parts =a transmitter , a detector &a receiver

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Atharv Khandelwal 7 years, 1 month ago

Sonar stands for sound navigation and ranging. It is used to measure the depth of Sea &also to identify enemy submarine. It can also identify the shoals of fish and groups of other aquatic animals

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ANSWER

Aarushi's mother always squeezes water from wet clothes in the spinner of washing machine and then uses it to clean the floor. a)write the principle of the technique used in above mentioned process. b)write one more applications of this technique.

Posted by Mohd Hussain 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Gaurav Seth 7 years, 1 month ago

(a) Centrifugation's Principle : Denser particles are forced to the bottom and the lighter particles stay at the top when spun rapidly.

(b) Used in dairies to separate butter from cream.

(c) Multiple use of the available resources to avoid wastage.

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Three balls are A,B andC are kept in a straight line the separation between A and C is 1m and B is placed at Amit. Between them the masses of A,BAndC Are 100 g,200g and 300g . Find the net gravitational force on(a)A,(b)B and(c)C

Posted by ?????? ?? 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Gaurav Seth 7 years, 1 month ago

A ------ 0.50 m -------- B -------- 0.50 -------- C

Ma = 0.100 kg Mb = 0.200 kg Mc = 0.300 kg

Net gravitational force Fa on A is towards right side.
      Fa = G Ma Mb / 0.50² + G Ma Mc / 1.0²
           = 6.67 * 10⁻¹¹ * 0.100 [ 0.200/ 0.50² + 0.300 /1 ] N
           = 7.34 * 10⁻¹² N

Net gravitational force Fc on C is towards B, left side and its magnitude is equal to Fa ie., 7.34 * 10⁻¹² N

Net gravitational force on B is Fb & is towards C
Fb = G Mb [ Mc - Ma ]/ 0.50²
= 6.67 * 10⁻¹¹ * 0.200 * 0.200 * 4 = 1.07 * 10⁻¹¹ N

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ANSWER

Write steps to prepare a colloidal solution from starch.

Posted by Suraj Kumar 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Gaurav Seth 7 years, 1 month ago

Theory
Starch forms a lyophilic sol when water is used as the dispersion medium. The formation of sol is accelerated by heating. The starch sol can be prepared by heating starch and water at about 100°C. It is quite stable and is not affected by the presence of any electrolytic impurity.

Apparatus
Beakers (250 ml and 50 ml), glass rod, funnel, filter-paper, pestle and mortar, tripod stand, wire-gauze and burner.

Materials Required
Soluble starch (500 mg) and distilled water.

Procedure

Take 500 mg of starch in a mortar and add few ml of distilled water.
Grind the starch to make a thin paste and transfer this paste to a 50 ml beaker.
Take about 100 ml of distilled water in a 250 ml beaker and heat the beaker so that water starts boiling.
Pour the paste slowly with stirring into boiling water in the beaker (Fig. 2.1).
Continue boiling for about 10 minutes and there allow the beaker to cool.
Filter the contents of the beaker through a filter-paper, fixed in a funnel.
Label the filtrate ‘Starch Sol’.

Precautions

The apparatus used for preparing sol should be properly cleaned.
Distilled water should be used for preparing sols in water.
Starch should be converted into a fine paste before adding to boiling water.
Starch paste should be added in a thin stream to boiling water.
Constant stirring of the contents is necessary during the preparation of the sol.

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Some fungal species live in permanent mutually dependent relationship with cynobacteria

Posted by Prince Yadavas 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Paridhi Sharma 7 years, 1 month ago

Yes. Some fungal species live in permanent symboitic relationship with cynobacteria known as lichens

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Normal temperature and pressure one water sample boils at 373K temperature. Is water pure? Is these water made ice at 273K temperature? Explain

Posted by Hari Patel 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Pratyusha Samantaray 7 years, 1 month ago

Yes ,this water is pure as it boils at normal temperature. Water which contains impurities will boil at a temperature less than 373 K or more than 373 K. Since, this water don't contains any impurities it will make ice at 273K.

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ANSWER

State the law of conservation of mass?(only correct answer plz .....)

Posted by Akhil Bajaj 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Suraj Kumar 7 years, 1 month ago

According to law of conservation of mass-The total mass of reactant is always equal to the total mass of product.

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A lamp containing 3.011*10^23 atoms of silver in it. What is the mass of silver lamp and the cost of if one gram silver cost ₹60.

Posted by Suman Gautam 7 years, 1 month ago

CBSE > Class 09 > Science

0 answers

ANSWER

Name the carbon compound which is responsible for the diplition of ozone layer

Posted by Babita Singh 7 years, 1 month ago

CBSE > Class 09 > Science

3 answers

Huzefa Khan 7 years, 1 month ago

Chloroflorocarbon

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Sneha Choudhury 7 years, 1 month ago

CFCs (chloro floro carbon)

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Akhil Bajaj 7 years, 1 month ago

Chloroflorocarbon .

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ANSWER

State the law of floatation

Posted by Khan Kaif 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Amrita Yadav 7 years, 1 month ago

According to law of floation , If the density of object is greater than density of fluid then the object will sink. If it's density is less than fluid then it will float and if equal then it will partially float in the fluid.

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ANSWER

why mitochondria is known as the power house of the cell.

Posted by Supriya Pathak 7 years, 1 month ago

CBSE > Class 09 > Science

3 answers

Srishti Agarwal 7 years, 1 month ago

Mitochondria is called the powerhouse of the cell because inside the cell glucose is broken down by oxygen to produce energy.

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Sneha Choudhury 7 years, 1 month ago

Becoz it provides energy in form of ATP (adensione triphosphate) to perform all activities needed for our life. And stores energy during respiration.Hence it is called power house Of the cell

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Rohit Singh 7 years, 1 month ago

Oxidation of food takes place in mitrochondria , and they release energy in various chemical activites needed for life ,Hence mitrochondria are known as powerhouse of cell

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Difference between distillation & fractional distillation

Posted by Somya Garg 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Meghna Thapar 6 years, 1 month ago

Distillation is used for the separation of components of a mixture containing two miscible liquids which boil without decomposition and have a sufficient difference in their boiling points. Whereas fractional distillation is used for the separation of a mixture containing two miscible liquids, for which the difference in their boiling points is less than 25^o C.

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What is latent heat of vaporisation?

Posted by Shivam Rai 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Srishti Agarwal 7 years, 1 month ago

Latent heat of vaporisation is the amount of heat energy required to convert 1 kg of liquid to gas without changing its tenperature.

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Somya Garg 7 years, 1 month ago

Water vapour (say100°) have more energy than waterat the same temperature. This is because particles in steam have absorbed extra enery in the form of latent heat of vaporisation

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What is Rutherford Model of an atom?

Posted by Shivam Rai 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Abhimanyu Paswan 7 years, 1 month ago

Rutherford's model shows that an atom is mostly empty space, with electrons orbiting a fixed, positively charged nucleus in set, predictable paths.

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ANSWER

Calculate the number of Moles of Nach in 200g of sodium chloride

Posted by Shivam Rai 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Saurabh Bisht 7 years, 1 month ago

no. Of moles = given mass /molar mass (This is the formula for calculating moles) Given mass is denoted by W. Molar mass is denoted by M. W= 200g M= mass of sodium+mass of chloride = 23+35.5 =58.5 u Now, n=W/M =200/58.5 =3.41 moles Hope this will help you .... Plz subscribe GAMING FREAKS.......

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Chlorine and magnesium ka chemical formula kya hai ?

Posted by Anshu Verma 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Lokesh Nainani 7 years, 1 month ago

Chemical formula of the following are : Chlorine =Cl Magnesium =Mg

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Abhyanand 7 years, 1 month ago

Chlorin cl and magnesium mg

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ANSWER

Draw the atomic structure of an atom having atomic no. 11 and mass no. 23

Posted by You Tubers 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Abhyanand 7 years, 1 month ago

1s2 2s2 2p6 3s1 and formula sodium (Na)

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Why Mitochondriya and plastids are called semi-autonomous organelles?

Posted by Lokesh Nainani 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Sirsti Sngm 7 years, 1 month ago

Mitochondria and plastids are semi autonomous body because they have thier own DNA and energy but they depends on nucleus for some enjymes.

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ANSWER

Dispherse phase and medium of rubber and chese and jemstone????????

Posted by Biswa Ranjan Bagarty 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Yashwanth R 7 years, 1 month ago

Dispersed Phase Dispersed Medium Rubber Gas Solid Cheese Liquid Solid Gemstone Solid Solid

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State the law of conservation of energy and verify it during the freefall of a body?? Long type answer please???

Posted by Biswa Ranjan Bagarty 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Sirsti Sngm 7 years, 1 month ago

According to the law of conservation of energy , energy is niether created nor destroyed.It meant that energy cant be created nor be destroyed but it could be transferred. For example in a light bulb the electrical energy transforms into heat energy which makes the bulb glow. During a free fall a body was when stationary it poses potential energy due to it's hight and stationary position but when it starts falling then it poses kenetic energy due to its moving position and again when the body reaches ground it's velocity decreases and at a particular time it gains zero velocity and then the body again gets potential energy .

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Define chemical compound

Posted by Rounak Singh 7 years, 1 month ago

CBSE > Class 09 > Science