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Sound is measure by what

Posted by Adarsh Baibhav 4 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Yash Thakkar 4 years, 5 months ago

Decibels

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how does amoeba prepared their food?

Posted by Mamta Sharma 4 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Komal Gadkar 4 years, 5 months ago

Here is your answer mamta sharma Amoeba is a protozoa and eukaryotic organism and it a heterotropic organism it engulfs its food from external environment through pseudopodia that is it intakes its food from the region of higher consentration to lower concentration. Hope it helps you

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Why did animal s fastest

Posted by Arman Khan 4 years, 5 months ago

CBSE > Class 09 > Science

0 answers

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Sound is measured by using WHAT?

Posted by Malavika Sr 4 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Nidhi Dhariwal 4 years, 5 months ago

Sound is measured by using 'Decibels'.

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What is the full form of DNA and what are the functional segements of DNA called?

Posted by Vansh Sharma 4 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Nidhi Dhariwal 4 years, 5 months ago

DNA = Deoxyribo Nucleic Acid functional segements of DNA are called Genes . Genes are the unit of inhertiance. Genes contains the characterstics of parents which comes in a offspring or baby from it's parents.

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Krishna Shashwat 4 years, 5 months ago

Full form of of DNA is called Deoxyribonucleic Acid. Its functional segments is called Genes.

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Why series arrangement not used for connecting domestic electrical appliances in a circuit ?

Posted by Veena Nautiyal 4 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 4 years, 5 months ago

A series arrangement is not used for connecting domestic electrical appliances in a circuit because if one electrical appliance stops working due to some defect, then all other appliance also stop working as the whole circuit is broken.

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Under what codition can a body travel a certain distance and yet its resultant diaplacement be zero

Posted by Aparna Singh 4 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 4 years, 5 months ago

If the body starts from a place and returns back to the starting point.
For ex. In a circular path around a park, if a jogger starts from point A, takes a round of the park and returns back to point A, then his resultant displacement will be 0.

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What do you mean division of labour?

Posted by Vansh Sharma 4 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 4 years, 5 months ago

Division of Labour means that the main process of production is split up into many simple parts and each part is taken by different workers who are specialised in the production of that specific part.

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Why solids have minimum power of attraction

Posted by Devanshu Ladwal 4 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Yogita Ingle 4 years, 5 months ago

Because of great force of attraction particles of solids are closely packed together. This makes the space between particles of solids almost negligible. The lowest kinetic energy of particles does not able to move the particles of solids.

Hence, the great force of attraction and least space between particles of solids and lowest kinetic energy of particles keep the particles at fixed places. Because of the combination of these characters matter exists in solid state.

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Devanshu Ladwal 4 years, 5 months ago

Please answer my question

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What happens when Zinc is dipped in copper sulphate solution

Posted by Mohith Cp 4 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 4 years, 5 months ago

When zinc plate is dipped copper sulphate solution,zinc sulphate is formed and copper is deposited on zinc strip. This reaction shows that zinc is more reactive than copper as it displaces copper from its solution and zinc passes into solution as zinc ions and zinc sulphate solution is formed

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How can we define interia

Posted by Mohith Cp 4 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 4 years, 5 months ago

Inertia is the natural tendency of an object to resist a change in its state of motion or of rest.
The mass of an object is a measure of its inertia.
A force that is just enough to cause a small cart to pick up a large velocity will produce a negligible change in the motion of a train, because of train’s large inertia.

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What is velocity??

Posted by Shivansh Raj 4 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Sameer Verma 4 years, 5 months ago

The distance travelled by a body per unit time in given direction

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Yogita Ingle 4 years, 5 months ago

The meaning of velocity of an object can be defined as the rate of change of the object’s position with respect to a frame of reference and time.

It is a vector quantity, which means we need both magnitude (speed) and direction to define velocity. The SI unit of it is meter per second (ms^-1) if there is a change in magnitude or the direction in the velocity of a body the body is said to be accelerating.

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Do molecules blast due to pressure

Posted by Mohith Cp 4 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Mayank Yadav 4 years, 5 months ago

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Derive the formula of conservation of momentum?

Posted by Anant Kumar Singh 4 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Meghna Thapar 4 years, 5 months ago

According to the law of conservation of momentum, the sum of momenta of two objects before collision is equal to the sum of momenta after collision, provided there is no external unbalanced force acting on the objects.

Suppose two balls A and B, of masses m_A and m_B are travelling in the same direction along a straight line at different velocities u_A and u_B. And there are no other external unbalanced forces acting on them. Let u_A > u_B and the two balls collide with each other. During collision which lasts for a time t, the ball A exerts a force F_AB on ball B and the ball B exerts a force F_BA on ball A.

Suppose v_A and v_B are the velocities of the two balls A and B after the collision, respectively.

The momenta of ball A before and after the collision are m_A u_A and m_A v_A. The rate of change of its momentum (or F_AB, action) during the collision will be

m_A (v_A - u_A)/t

Similarly, the rate of change of momentum of ball B (= F_BA or reaction) during the collision will be

m_B (v_B - u_B)/t.

According to the third law of motion, the force F_AB exerted by ball A on ball B (action) and the force F_BA exerted by the ball B on ball A (reaction) must be equal and opposite to each other. Therefore,

F_AB = – F_BA

m_A (v_A - u_A)/t = -m_B (v_B - u_B)/t. This gives,

m_A u_A + m_B u_B = m_A u_A + m_B v_B

where m_A and m_B are masses of the bodies, u₁ and u₂ are initial velocities of the bodies and v₁ and v₂ are final velocities of the bodies.

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e = mc2 .What does c stand for

Posted by Harshit Srivastav 4 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Yash Thakkar 4 years, 5 months ago

C stands for speed of light

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Lakshika Tayal 4 years, 5 months ago

C stands for Speed of light

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What is scaler and vector

Posted by Aman Parmar 4 years, 5 months ago

CBSE > Class 09 > Science

5 answers

Sameer Verma 4 years, 5 months ago

Scalar quantity It is a physical quantity having only magnitude nor direction Example speed , distance

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Bajendra Narayan Sahoo 4 years, 5 months ago

all those quantity which can completely described by magnitude alone is called scalar quantity and vector is those quantity have both magnitude and direction are called vector quantity

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Kumar Adarsh 4 years, 5 months ago

All those quantity which can completely described by magnitude alone is called scalar

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Harsh Kumar 4 years, 5 months ago

Those quantity have both mangitud and direction are called vectors

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Harsh Kumar 4 years, 5 months ago

Those quantity have only mangitude are called scalar quantity

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A tortortise move 100 m in 15 sec

Posted by Anurag Maurya 4 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Bajendra Narayan Sahoo 4 years, 5 months ago

Please correct question

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Harshit Srivastav 4 years, 5 months ago

Please write complete question

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Is matter continuous?

Posted by Sanket 4 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Harshit Srivastav 4 years, 5 months ago

However, there is another nature associated with matter, which is wave like nature. You will study about this in more detail in grade 11, where an entire chapter has been devoted to this. Sub-atomic particles like electrons very well exhibit wave nature along with particle nature. However this wave nature is not shown by macroscopic objects which are easily observable. The wavelength that is associated with these objects is too small and not appreciable.

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Harshit Srivastav 4 years, 5 months ago

Matter is composed of very small particles called atoms, hence matter is not continuous but particulate in nature.

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Water is liquid at room temperature. Give reason

Posted by Shubham Rathi 4 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Harshit Srivastav 4 years, 5 months ago

ANSWER (a) Water at room temperature is a liquid because it boils at 373 K and the room temperature is nearly 20 ∘ C−25 ∘ C. The solidification point is 0 ∘ C It will remain in a liquid state. It does not have a definite shape but has a definite volume at room temperature. So these are properties of a liquid state.

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Yogendra Singh 4 years, 5 months ago

Yes

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Differentiate between nucleus and nucleoid?

Posted by Palak Burman 4 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Meghna Thapar 4 years, 5 months ago

A nucleus is a membrane-bound organelle that houses the genetic material of eukaryotes in DNA. The nucleus consists of protein fibres or the DNA inside chromatin fibres. Nucleoids contain the genetic material of prokaryotes in the cytoplasm.

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Why is nucleus called director of the cell?

Posted by Palak Burman 4 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Krishna Shashwat 4 years, 5 months ago

Nucleus is called director of the cell because it controls each part of the cell. It directs each thing in its own way. Nucleus is one which is also called by Boss of cell.

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Why does the skin of your fingers shrink when you wash clothes for a long time?

Posted by Palak Burman 4 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Meghna Thapar 4 years, 5 months ago

When we wash clothes, our hands are exposed to water for a long time. Our hands behave as hypertonic solution and the outside of our hands behave as hypotonic solution. Hence, water flows from high concentration to low concentration. The water is not entering your hands, it actually leaves them and hence, they shrink.

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How do substances like CO2 and water move into and out of the cell? Discuss.

Posted by Palak Burman 4 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Meghna Thapar 4 years, 5 months ago

The substances like CO2 and water move in and out of a cell by diffusion from the region of high concentration to low concentration. When the concentration of CO2 and water is higher in external environment than that inside the cell, CO2 and water moves inside the cell.

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NH3+O2= N2 + H2O Balance the following equation

Posted by Samruddhi Br 4 years, 5 months ago

CBSE > Class 09 > Science

0 answers

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A soft drink hashas to ve cooled......

Posted by Sk Gamer 4 years, 5 months ago

CBSE > Class 09 > Science

0 answers

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A stone is thrown in a vertically upward direction with a velocity of 5ms^-1. If the acceleration of stone during its motion is 10 ms^-2 in the downward direction, what will be the height attained by the stone and how much time will it take to reach there?

Posted by Harman Brar Brar 4 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Sia ? 3 years, 4 months ago

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Measure the time taken you from your school to your bus stop for the school if you consider that a average walking speed is 4 kilometre as -1 eliminate distance of bus stop or school from your house

Posted by Sangay Sherpa Sherpa 4 years, 5 months ago

CBSE > Class 09 > Science

0 answers

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How reproduction is done?

Posted by Bajendra Narayan Sahoo 4 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Bajendra Narayan Sahoo 4 years, 5 months ago

Thanks

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Meghna Thapar 4 years, 5 months ago

Human reproduction is any form of sexual reproduction resulting in human fertilization. It typically involves sexual intercourse between a man and a woman. During sexual intercourse, the interaction between the male and female reproductive systems results in fertilization of the woman's ovum by the man's sperm.

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Best painting

Posted by Pragya Pathak 4 years, 5 months ago

CBSE > Class 09 > Science