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To draw a lab Observe the action of zinc iron copper and aluminum metal on the following salt solution

Posted by Rashmi Ranjan 5 years ago

0 answers

ANSWER

two resistances X and Y are connected turn by turn : i) in parallel and ,ii)in series. In which case the resultant resistance will be less than either of the individual resistances?

Posted by Arnav Kedia 5 years ago

CBSE > Class 10 > Science

5 answers

Nisha Kumari 5 years ago

In Parallel connection of resistance will be less than series connection because dividing becomes in parallel which is 1/R +1/R2 which causes it becomes less .

1Thank You

Shubh Madheshiya 5 years ago

In parallel combination

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Mouli Mandal 5 years ago

In parallel combination, the resultant resistance will be less .Req in parallel combination is less than each individual resistor whereas in series the Req is sum of all resistors which is always great than individual values.

3Thank You

Xxx Xxx 5 years ago

It will be less when connected in parallel beacuse to obtain maximus resistance the resistors must be connected in series and the total resistance will be the sum of X and Y. But in parallel conection the resultant resistance will be the the sum of the reciprocals of X and Y. i.e 1/R = 1/R1 + 1/R2

1Thank You

Khushi 5 years ago

In case of parallel combination , the resultant resistance will be less than either of the individual resistances . It is because, the net resistance in series is simply the sum of all resistances but in cases of parallel combination, it is the reciprocal of the sum of the reciprocals of all resistances. i.e. 1/ Req = 1/R1 + 1/R2

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ANSWER

Which organ is helping to taste

Posted by Prem Prakash 5 years ago

CBSE > Class 10 > Science

5 answers

P.Mohana Sri Premnath 5 years ago

Tongue is the organ used to taste

2Thank You

Himani Chaudhary 5 years ago

Tongue

3Thank You

Shreya Shresty 5 years ago

Tongue

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Ch. Nandini 5 years ago

???????

2Thank You

Prem Prakash 5 years ago

Tongue

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ANSWER

What can be seen when a strip of copper metal is placed in a solution of silver nitrate

Posted by Raj Kumar 5 years ago

CBSE > Class 10 > Science

2 answers

Mouli Mandal 5 years ago

Cooper lies above silver in the reactivity series. So, it will displace silver from it's salt solution and hence form copper nitrate and silver metal.

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Himani Chaudhary 5 years ago

Answer:When a 'strip of copper metal' is placed in a 'silver nitrate' solution, a greyish white deposit ofsilver can be seen of thecopper strip. EXPLANATION: This happens because 'copper' is more reactive than 'silver' and displaces silvereasily to form copper nitrate.

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ANSWER

How stars twinkling

Posted by Tapesh Mandal 5 years ago

CBSE > Class 10 > Science

5 answers

Ishika Kumari 5 years ago

Sorry refraction

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Ishika Kumari 5 years ago

They are twinkling due to atmospheric pressure or retraction

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Rhythem Ias 5 years ago

Atmospheric refraction :-Main phenomenon responsible for this observation

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Krishna Bhagat 5 years ago

The change in intensity of light coming from the stars is called twinkling of stars. The twinkling of stars occurs due to atmospheric refraction of star's light. Hence, the star light reaching our eyes change continuously and stars appear to twinkle.

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Ch. Nandini 5 years ago

When light from a distant source (a star) passes through our turbulent (moving air) atmosphere, it undergoes refraction many times. ... This is because some of the light rays reach us directly and some bends away from and toward us. It happens so fast that it gives a twinkling effect

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Imagine that you are sitting in a chamber with your back to one wall .An election beam moving horizontally from back wall towards the front wall is deflected by a strong magnetic field to your right side.What is the direction of magnetic field?

Posted by Maibam Sneha 5 years ago

CBSE > Class 10 > Science

1 answers

Mouli Mandal 5 years ago

Magnetic field will be in downward direction.

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When a green colour compound is heated strongly it colour change to black and odour of burning is given out .( 1) name the compound (2)state types of reaction (3) write balance equation

Posted by Pravat Rout 5 years ago

CBSE > Class 10 > Science

1 answers

Khushi 5 years ago

⑴ The given compound is FeSO4. ⑵ Thermal decomposition . ⑶ 2FeSO4→Fe2O3 + SO2 ↑ + SO3 ↑

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How to find charge on a element

Posted by Sahil Garg 5 years ago

CBSE > Class 10 > Science

2 answers

Yutee Dhakate 4 years, 11 months ago

The charge of an element is equal to the number of protons plus the number of electrons

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Anvesh Guptha 5 years ago

The charge of an element is equal to the number of protons minus the number of electrons.

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ANSWER

How to find parallel and series resistance in a circuit?

Posted by Taniya 5 years ago

CBSE > Class 10 > Science

2 answers

Aanya Jain 5 years ago

To find out resistance of resistors in series combination: R=R1+R2+ R3 Parallel combination 1/R =1/R1 +1/R2 +1/ R3

1Thank You

Rohit Singh 5 years ago

You have learn formula and derivation for it its formula for parallel: 1/R=1/R1+1/R2+1/R3 For series:R=R1+R2+R3

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ANSWER

2 Feb 2020-21ko board ka time table aane wala h kitane bhj aaye ka kisi ko pta h Kya

Posted by Krazy Girl 5 years ago

CBSE > Class 10 > Science

3 answers

Ch. Nandini 5 years ago

??????? ???

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Krazy Girl 5 years ago

Haa

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Muskan Kumari 5 years ago

Aa to gya

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ANSWER

How many number of electrons are there in one micro-ampere?

Posted by Arpita Tejpal 5 years ago

CBSE > Class 10 > Science

2 answers

Arun Raj 5 years ago

6.25 ×10^12

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Khushi 5 years ago

6.25 ×10¹²

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Tell me Differece between ELECTRIC POTENTIAL AND POTENTIAL DIFFERENCE

Posted by Tushar Sharma 5 years ago

CBSE > Class 10 > Science

2 answers

Aanya Jain 5 years ago

Electrical potential is the amount of work done to carry one coloumb of charge from infinity to other point in an electrical field. Potential difference is the amount of work done to transfer one coloumb charge from one coloumb of charge from one point to another in an electrical field

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Priya Tomar 5 years ago

The electrical potential difference is defined as the amount of work done to carrying a unit charge from one point to another in an electric field. In other words, the potential difference is defined as the difference in the electric potential of the two charged bodies. Unit: The unit of potential difference is volt.

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What is snells law ?

Posted by Pranav Chaudhary 5 years ago

CBSE > Class 10 > Science

2 answers

Priya Tomar 5 years ago

Snell's law, in optics, a relationship between the path taken by a ray of light in crossing the boundary or surface of separation between two contacting substances and the refractive index of each.

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Tushar Sharma 5 years ago

According to Snell's law of refraction the sin of angle of incident to the sine of the angle of refraction always constant this constant called as Refractive Index

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What is electronegativity and electropositivity

Posted by Mohit Malviya 5 years ago

CBSE > Class 10 > Science

2 answers

Nisha Kumari 5 years ago

Which element loss the electron from outermost orbit for becomes stable is called electropositive. Which element gain the electron from outermost orbit for becoming stable is called electronegative.

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Suman Kumar 5 years ago

The elements which gain electrons to complete their octet is called electronegative elements. This property is found in non - metals . And this property of gaining electrons in order to complete their octet is called electronegativity. And in metals this is vice versa. The property of loosing electrons by metals in order to fulfill their octet is called electropositivity.

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ANSWER

What are trends in the periodic table ?

Posted by Mohit Malviya 5 years ago

CBSE > Class 10 > Science

1 answers

Kapil Mahajan 5 years ago

Trend means the order which came into play after arrangement of elements in certain order. For example their size from 1 to 20th element, their chemical behaviour etc

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ANSWER

What is villi and function

Posted by Himanshu Gurjar 5 years ago

CBSE > Class 10 > Science

5 answers

Nisha Kumari 5 years ago

Vilia is the part of the small intestine which absorb the nutrients and send the nutrients all the body parts through blood vessels.

1Thank You

Arun Raj 5 years ago

Villi is a finger like projection inside small intestine. It increases the surface area to increase the absorption of food

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Tushar Sharma 5 years ago

VILLI PRESENT IN SMALL INTESTINE THAT INCREASE THE SURFACE AREA OF INTESTINE TO ABSORBED FOOD

2Thank You

Riya Surniyal 5 years ago

Finger like projection inside small intestine is called villi.Their function is to increase the surface area in order to maximise the absorption of digested food

4Thank You

Harshdeep Singh 5 years ago

Don't know

3Thank You

ANSWER

Why in vibgyor only seven colors

Posted by Himanshu Gurjar 5 years ago

CBSE > Class 10 > Science

5 answers

Ch. Nandini 5 years ago

??????? ????? ????? ??????? ????? ????? ???? 7 ??????? ???? ???? ??????? ???? ???? ????????

1Thank You

Ajay Kumar 5 years ago

Rainbows appear in seven colors because water droplets break sunlight into the seven colors of the spectrum. You get the same result when sunlight passes through a prism.

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Tushar Sharma 5 years ago

White light consist of only 7 colours so that.....

1Thank You

Abhishek Panda 5 years ago

White light consists only seven colour.

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Manish ???? 5 years ago

Vibgyor is short form of seven colour s

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ANSWER

How an organism be benefited if reproduced by spores.

Posted by Daksh Saini 5 years ago

CBSE > Class 10 > Science

1 answers

Good Day 5 years ago

Answer Reproduction through spores gives several advantages to an organism. Some of them are as follows: Spores can remain dormant till favourable conditions become available. Spores help an organism to tide over the bad phase. Spores can be spread through water, air or animals and thus is good for the spread of an organism to more places.

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ANSWER

Why Vegetative Propagation needed for growing some plants.

Posted by Daksh Saini 5 years ago

CBSE > Class 10 > Science

2 answers

Tushar Sharma 5 years ago

Seedless k liye

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Good Day 5 years ago

Vegetative propagation is practiced for growing some types of plants because of following advantages: It helps to introduce plants in new areas where seed germination fails to produce mature plants due to changes in environmental factors and the soil. It is a more rapid, easier, and cheaper method. Produces identical quality as the parent. Faster and more certain methods of propagation.

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ANSWER

In which website we can download together with (15+1) latest sample papers 2020-2021 Please tell

Posted by Vaibhav Pandey 5 years ago

CBSE > Class 10 > Science

1 answers

Vaibhav Pandey 5 years ago

Pdf

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Blue colour flower plant denoted by BB in cross breed with that of white colour flower plant denoted by bb. 1) state the colour of flower you would expect in their F1 generation plants. 2) what must be the percentage of white flower plants in F2 generation if flower of F1 plants are self pollinated. 3) state the expected ratio of genotypes BB and Bb in F2 progeny.

Posted by Daksh Saini 5 years ago

CBSE > Class 10 > Science

5 answers

???????⚫ ⚪ 5 years ago

1)blue colour plants will be obtained in F1 generation 2)25% 3)BB:Bb=1:2

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Ch. Nandini 5 years ago

3:1

0Thank You

Sarthak?? Jaiswal 5 years ago

For F2 generation

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Sarthak?? Jaiswal 5 years ago

1:2

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Sarthak?? Jaiswal 5 years ago

Bb Bb Bb Bb in F1 generation

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ANSWER

What are the mode of nutrients in amoeba

Posted by Derhasat Ramchiary 5 years ago

CBSE > Class 10 > Science

4 answers

Sarthak?? Jaiswal 5 years ago

Holozoic mode of nutrition

2Thank You

Ritesh Rana 5 years ago

Heterotrophic

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Anuj Agrawal 5 years ago

Holozoic

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Khushi 5 years ago

The mode of nutrition in amoeba is known as holozoic nutrition. It involves the ingestion, digestion and egestion of food material.

3Thank You

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What is the difference between ionic bond and covalent bond

Posted by La_Me Opsie? 5 years ago

CBSE > Class 10 > Science

5 answers

Yashika Lakra 5 years ago

Ionic means giving an electron completely nd covelent means sharing of electrons

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Arun Raj 5 years ago

Bonds form by transfer of electron from one metal to another non metal is called ionic bond Bonds formed by sharing of an electron is called covalent bond

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Prithviraj Godara 5 years ago

IONIC COMPOUND = THIS TYPE OF COMPOUND FORMED BY TRANSFER OF ELECTRONE FROM METALS TO NON- METALS. EX- NACL COVALENT BOND = THIS TYPE OF BOND FORMED BY SHARING OF ELECTRONS. EX- CARBON COMPOUND IS EXAMPLE OF COVALENT COMPOUND. THANKS - PRITHVIRAJ GODARA (SCIENCE TEACHER )

2Thank You

Good Day 5 years ago

Ionic bond is formed by transferring of electron but covalent bond is formed by sharing of electron.

2Thank You

Anya Goyal 5 years ago

Ionic bond includes gaining or losing of electron to gain positive or negative charge. Covalent bond is the sharing of electron, In Covalnet bond tlno charge is obtained.

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ANSWER

in what forms metal is found in nature with the help of Example explain how metals react with oxygen and water and dilute acid also write chemical equation for the reaction

Posted by Henshi Bhudiya 5 years ago

CBSE > Class 10 > Science

2 answers

Good Day 5 years ago

Metals are found in free State in nature. Example gold, silver etc. When metals react with oxygen it form oxide. 2Mg + O2 = 2MgO When metal react with water it form hydroxide and hydrogen gas. 2Na + 2H2O= 2NaOH + HE When metal react with dillute acid it form salts and hydrogen gas. Mg + 2HCl =MgCl2 + H2

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Anuj Agrawal 5 years ago

Metals are found are free state in nature...Ex: Gold, silver, platinum

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_________ is a non-metal which is lustrous.

Posted by Khushi 5 years ago

CBSE > Class 10 > Science

5 answers

Prithviraj Godara 5 years ago

IODINE IS A NON-METAL WHICH IS LUSTROUS. -GENERALLY, NON-METALS ARE NON LUSTORS. BUT IODINE IS EXCEPTION. SO THAT IODINE IS NON-METAL BUT LUSTORS. THANKS PRITHVIRAJ GODARA ( SCIENCE TEACHER )

1Thank You

Good Day 5 years ago

Iodine

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Sarthak?? Jaiswal 5 years ago

Iodine and diamond both

3Thank You

Rock Ayush Gupta 5 years ago

Iodine is the right answer

3Thank You

Anuj Agrawal 5 years ago

Iodine

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ANSWER

Name the gas evolved when dilute HCl reacts with sodium hydrogen carbonate. How is it recognised ?

Posted by Manu Battineni 5 years ago

CBSE > Class 10 > Science

2 answers

Arun Raj 5 years ago

Carbon dioxide gas is evolved. To test it we pass this gas through lime water and it turns it milky

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Khushi 5 years ago

When dilute HCI reacts with sodium hydrogen carbonate Carbon dioxide gas is evolved. We pass this gas through lime water it turns milky because of the CO2 passing through it . If we keep on passing the gas through milky lime water, it would become clear again.

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Explain activity to show that current carrying conductor experiences force when placed the magnetic field

Posted by Arman Singh 5 years ago

CBSE > Class 10 > Science

1 answers

Aziz Fatima 5 years ago

Take an aluminum rod AB. Suspend it using two connective wires and connect it in series with battery and a key. Place a magnet such that rod lies between the two poles of magnet. And such that the Noth pole of magnet lies above end B and it's South Pole lie below the end A. Switch the key and pass the current. It will be observed that the rod is displaced towards the left Thus it is displaced because the rod when placed in a magnetic field has experienced a force die to which it gets displaced.

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Why are ionic compounds usually hard ?

Posted by Khushi 5 years ago

CBSE > Class 10 > Science