CBSE > Class 10 > Science | CBSE Board | Homework Help

This equation is a Quadratic equation (in form a x 2 + b x + c = 0 ) Use the Quadratic formula: x = − b ± √ b 2 − 4 a c 2 a In this case a = 1 , b = 2 , c = − 7 Substitute the values: → x = − 2 ± √ 2 2 − 4 ( 1 ) ( − 7 ) 2 ( 1 ) → x = − 2 ± √ 4 − ( − 28 ) 2 → x = − 2 ± √ 4 + 28 2 → x = − 2 ± √ 32 2 → x = − 2 ± √ 16 ⋅ 2 2 → x = − 2 ± 4 √ 2 2 → x = − 2 2 ± 4 √ 2 2 → x = − 2 2 ± 4 √ 2 2 ⇒ x = − 1 ± 2 √ 2

0Thank You

Parth Chaturvedi 4 years, 1 month ago

roots or zeroes of the given eq. are imaginary

2Thank You

Sachin Parmar 4 years, 1 month ago

Caco³+co²

4Thank You

ANSWER

Any1 needs help?

Posted by Raj Nandini Chouhan? 4 years, 1 month ago

CBSE > Class 10 > Science

0 answers

ANSWER

Explain about the circulatory system in human

Posted by Aafreen S 4 years, 1 month ago

CBSE > Class 10 > Science

1 answers

Priyanshi Attrish 4 years, 1 month ago

The circulatory is a complex process that occurs in multi cellular organisms like human being,animals etc... The oxygenated blood from lungs goes to the left atrium through the pulmonary vein.. The oxygenated blood goes from left atrium to the left ventricle through the valves present in our heart... Than the oxygenated blood goes from the left ventricle to the organs of our body through the main artery known as aorta. The oxygenated blood used in our body and the deoxygenated blood from organs of our body goes to the right atrium through the main vein known as vena cava. The deoxygenated blood from the right atrium goes to the left ventricle through the valves present in our heart.. Finally the deoxygenated blood from the left ventricle goes back to the lungs through the pulmonary artery.. Finally the deoxygenated blood is gone out from our body and again oxygenated blood comes and this process again occurs in our heart.. The heart is made up of special muscle known as cardic muscle.. Hope it's helpful for u ???

2Thank You

ANSWER

The milk obtained from a milkman requires more time to set into curd . Why ?

Posted by Mansi Shehrawat 4 years, 1 month ago

CBSE > Class 10 > Science

3 answers

Parth Chaturvedi 4 years, 1 month ago

Depends upon honesty of your milkman

1Thank You

Naghma Talat 4 years, 1 month ago

The milk obtained from milkman contains baking soda , which makes the milk more basic and since for milk to convert to curd ,it needs to be an acidic medium , so it takes more time for lactobacillus to convert milk to curd .

2Thank You

Aditi Sheth 4 years, 1 month ago

Because the amount of water is more than the amount of milk , So , Milk obtained from a milkman requires more time to set into curd...

0Thank You

ANSWER

What happens when gypsum is over heating ?

Posted by Mansi Shehrawat 4 years, 1 month ago

CBSE > Class 10 > Science

3 answers

Avnish Prajapat 4 years, 1 month ago

It's make plaster of Paris

0Thank You

Priyanshi Attrish 4 years, 1 month ago

If gypsum is over heat than it brust in the air It's requires a perfect Temperature that is 273k..

0Thank You

Naghma Talat 4 years, 1 month ago

If gypsum is over heated all its water of crystallization vapourizes making it anhydrous ( without water ) which is no longer it use , and becomes a waste product

0Thank You

ANSWER

Why do we add acid to water instead of water to acid ?

Posted by Mansi Shehrawat 4 years, 1 month ago

CBSE > Class 10 > Science

4 answers

Aishwarya Bagde 4 years, 1 month ago

When you add water to acid it is very explosive it is a exothermic reaction , it can also catch fire..

0Thank You

Haya Sikander 4 years, 1 month ago

We should always add acid to water with constant stirring instead of adding water to acid. The reason is that if we add water to acid the reaction that'll take place will be highly exothermic and hence can cause severe injury.

0Thank You

Priyanshi Attrish 4 years, 1 month ago

If we add water in acid it's brust out even when we add water in acid we have to shake that tube in which the acid is present because when water is added to acid drop by drop it's so high boiling point so it produces a lot of heat and there's a chances to expose but if u add acid in water so acid is so harmful and its expose in air that's why we never add water in acid

0Thank You

Anushka Tyagi 4 years, 1 month ago

When you mix acid with water, it's extremely important to add the acid to the water rather than the other way around. This is because acid and water react in a vigorous exothermic reaction, releasing heat, sometimes boiling the liquid. ... When you add water to acid, the water boils and the acid may splatter and splash!

1Thank You

ANSWER

Explain double displacement reaction.

Posted by Diya Shah 4 years, 1 month ago

CBSE > Class 10 > Science

3 answers

Priyanshi Attrish 4 years, 1 month ago

The reaction in which the compounds share each other ions and form a new product.this reaction is called double displacement reaction.. Example- HCL+NAOH ----- NACL+H2O In that reaction hcl and naoh displace And share each other ions ..

2Thank You

Mansi Shehrawat 4 years, 1 month ago

Those solutions in which two or more compounds react by an exchange of ions to form two new compounds are called double displacement reaction .

2Thank You

Gunjan Giri 4 years, 1 month ago

Double displacement reaction is the process in which two elements exchange each other ....

2Thank You

ANSWER

Acidic in nature

Posted by Anish Kumar 4 years, 1 month ago

CBSE > Class 10 > Science

4 answers

Aishwarya Bagde 4 years, 1 month ago

Non metals are acidic in nature.

0Thank You

Priyanshi Attrish 4 years, 1 month ago

Non metal are acidic in nature

0Thank You

Fs Ñøtês 4 years, 1 month ago

Acids

1Thank You

Avinash Singh 4 years, 1 month ago

Sour

0Thank You

ANSWER

Rays from sun converge at a point 15 cm in front of a concave mirror. Where should an object placed, so that it's image formed is equal to the size of the object?

Posted by Yograj Yadav 4 years, 1 month ago

CBSE > Class 10 > Science

3 answers

Priyanshi Attrish 4 years, 1 month ago

At 30 cm

0Thank You

Mansi Shehrawat 4 years, 1 month ago

At 30 cm front of the mirror

0Thank You

Kuldeep Dobwal 4 years, 1 month ago

At 30 cm front of the mirror

2Thank You

ANSWER

Sample work

Posted by Akash Gupta 4 years, 1 month ago

CBSE > Class 10 > Science

0 answers

ANSWER

What is prism define in detail.

Posted by Preet Srivastav 4 years, 1 month ago

CBSE > Class 10 > Science

1 answers

Priyanshi Attrish 4 years, 1 month ago

Prism is a triangular shape object which have refraction surface. Prism is just opposite to the rectangular glass slab.. prism splits the white light into seven colours that is known as Vibgyor.

0Thank You

ANSWER

What is the formula of hydrogen sulphate

Posted by Ajay Rajput 4 years, 1 month ago

CBSE > Class 10 > Science

5 answers

Avinash Singh 4 years, 1 month ago

H2so4

0Thank You

Kuldeep Dobwal 4 years, 1 month ago

H2SO4

1Thank You

Preet Srivastav 4 years, 1 month ago

H2So4

0Thank You

Naman Kumar 4 years, 1 month ago

H2so4

0Thank You

Vani Sharma 4 years, 1 month ago

H2so4

0Thank You

ANSWER

Form of iron

Posted by Rudra Jaiswal 4 years, 1 month ago

CBSE > Class 10 > Science

2 answers

Priyanshu Yadav 4 years, 1 month ago

Ooooooo. Nnb. Mi8o

0Thank You

Gunjan Giri 4 years, 1 month ago

There are three form of iron ..... iron 1 ,iron 2 ,iron 3

0Thank You

ANSWER

Assertion - refraction of white light through prism gives rise to the dispersion Reason - both the refracting surfaces of glass slab are parallel to each other but refracting surface area of prism are inclined to an angle called Angle of prism

Posted by Neha Singh 4 years, 1 month ago

CBSE > Class 10 > Science

2 answers

Dipu Singh 4 years, 1 month ago

0Thank You

Priyanshi Attrish 4 years, 1 month ago

Option b - both assertion and reason are correct but reason is not correct explaination of assertion

0Thank You

ANSWER

A dilute ferrous sulphate solution was gradually added to the beaker containing acidified perman- ganate solution. The light purple colour of the solution fades and finally disappears. Which of the following is the correct explanation for the observation? (A) KMnO4 is an oxidising agent, it oxidises FeSO4. (B) FeSO4 acts as an oxidising agent and oxidises KMnO4. (C) The colour disappears due to dilution; no reaction is involved. (D) KMnO4 is an unstable compound and decomposes in presence of FeSO4 to a colourless compound.

Posted by Prakriti Priya 4 years, 1 month ago

CBSE > Class 10 > Science

2 answers

Kuldeep Dobwal 4 years, 1 month ago

0Thank You

Ajay Rajput 4 years, 1 month ago

1Thank You

ANSWER

2. A dilute ferrous sulphate solution was gradually added to the beaker containing acidified perman- ganate solution. The light purple colour of the solution fades and finally disappears. Which of the following is the correct explanation for the observation? (A) KMnO4 is an oxidising agent, it oxidises FeSO4. (B) FeSO4 acts as an oxidising agent and oxidises KMnO4. (C) The colour disappears due to dilution; no reaction is involved. (D) KMnO4 is an unstable compound and decomposes in presence of FeSO4 to a colourless compound.

Posted by Prakriti Priya 4 years, 1 month ago

CBSE > Class 10 > Science

1 answers

Priyanshi Attrish 4 years, 1 month ago

It's correct option is A

0Thank You

ANSWER

Copper ,iron,zinc , Magnesium which of these are two combination reaction

Posted by Shad Ali Choudhary 4 years, 1 month ago

CBSE > Class 10 > Science

2 answers

Jisha Rawat 4 years, 1 month ago

And metal oxides are always basic in nature .

4Thank You

Jisha Rawat 4 years, 1 month ago

Combination reaction- it is a type of reaction in which two or more substitutes chemically combine together to form a single product . For example- Magnesium reacts with oxygen to give magnesium oxide . 2Mg+O2=2MgO

4Thank You

ANSWER

Practical of science

Posted by Ujjwal Kumar 4 years, 1 month ago

CBSE > Class 10 > Science

1 answers

Shree Singh 4 years, 1 month ago

All things about refraction of light and the formation of rainbow ??

0Thank You

ANSWER

Wavelength of red colour

Posted by Subhash Kumar 4 years, 1 month ago

CBSE > Class 10 > Science

5 answers

Manish Yaduvanshi 4 years, 1 month ago

????? ???????? ?????

0Thank You

Rishabh Yadav 4 years, 1 month ago

700 nm

2Thank You

Ujjwal Kumar 4 years, 1 month ago

High

1Thank You

Khushi Singh 4 years, 1 month ago

What is the colour of magnesium ribbon

2Thank You

Prakshi Vahista 4 years, 1 month ago

650

1Thank You

ANSWER

Under which mode of nutrition does amoeba come, holozoic, saprophytic or parasitic ?

Posted by Syed Owais 4 years, 1 month ago

CBSE > Class 10 > Science

5 answers

Dikshita Rathi 4 years, 1 month ago

Holozoic

0Thank You

Malladi Sriram 4 years, 1 month ago

Holozoic

0Thank You

Lalitha Lalitha 4 years, 1 month ago

Holozoic

0Thank You

Sneha Swami 4 years, 1 month ago

holozoic

0Thank You

Somansh Sarvesh 4 years, 1 month ago

Amoeba comes under holozoic mode of nutrition because there is ingestion then digestion..

0Thank You

ANSWER

Which property of light makes a pencil cast shadow when it is held in front of a light source?????

Posted by Trushti Parmar 4 years, 1 month ago

CBSE > Class 10 > Science

5 answers

Jisha Rawat 4 years, 1 month ago

It defraction of light that casts shadow of pencil . Because defraction is the phenomenon of bending of light around the object when an obstacle ( object) comes in the way of the ray of light .

1Thank You

Vyash S 4 years, 1 month ago

Reflection

0Thank You

Rohit Hitman 4 years, 1 month ago

Defraction of light

0Thank You

Trushti Parmar 4 years, 1 month ago

Thanks

0Thank You

Raj Nandini Chouhan? 4 years, 1 month ago

I think it's reflection Hope it may help

1Thank You

ANSWER

Give example of endothermic reaction?

Posted by Lovely Bhalla 4 years, 1 month ago

CBSE > Class 10 > Science

5 answers

Rohit Hitman 4 years, 1 month ago

Respiration inside human body

0Thank You

Pawandeep Kaur 4 years, 1 month ago

Melting of ice cubes

3Thank You

Anshit Jaiswal 4 years, 1 month ago

Evaporation of water

1Thank You

Komathi .R 4 years, 1 month ago

In which energy is absorbed is known as endothermic reaction Example : decomposition reaction chemical formula is 2AgBr(s)----------->2Ag(s)+Br2(g)

0Thank You

Tanisha Garg 4 years, 1 month ago

Photosynthesis reaction

4Thank You

ANSWER

Chemistry chapter 1 mcq based on activities

Posted by Saveena Bishnoi 4 years, 1 month ago

CBSE > Class 10 > Science

1 answers

Aishwarya Bagde 4 years, 1 month ago

https://www.learncbse.in/mcq-questions-for-class-10-science-chemical-reactions-and-equations-with-answers/

0Thank You

ANSWER

Mcq based on chapter 1 activities

Posted by Saveena Bishnoi 4 years, 1 month ago

CBSE > Class 10 > Science

2 answers

Aishwarya Bagde 4 years, 1 month ago

https://www.learncbse.in/mcq-questions-for-class-10-science-chemical-reactions-and-equations-with-answers/

0Thank You

Mayank Yadav 4 years, 1 month ago

0Thank You

ANSWER

The focal length of combination of convex lens of power 1 D and concave lens of power -1.5 D is

Posted by Pragya Sisodiya 4 years, 1 month ago

CBSE > Class 10 > Science

5 answers

Shree Singh 4 years, 1 month ago

200cm

0Thank You

Vyash S 4 years, 1 month ago

1Thank You

Pawandeep Kaur 4 years, 1 month ago

0Thank You

Lovely Bhalla 4 years, 1 month ago

2Thank You

Anjali Taehyung 4 years, 1 month ago

2Thank You

ANSWER

An object is placed at the centre of curvature of a concave lens. The distance between the image and the pole is * Equal to 2f * Greater than f but less than 2f * Equal to f *Greater and 2f

Posted by Sneha . K 4 years, 1 month ago

CBSE > Class 10 > Science

5 answers

Parth Chaturvedi 4 years, 1 month ago

You have written wrong as lens have optical centre not pole

0Thank You

Kuldeep Dobwal 4 years, 1 month ago

Equal 2f

0Thank You

Shree Singh 4 years, 1 month ago

Equal to 2f

0Thank You

Vanshika Joshi 4 years, 1 month ago

Equal to 2f

1Thank You

Yuvasree N 4 years, 1 month ago

Equal to 2F

0Thank You

ANSWER

Why sky is blue in day time

Posted by Saloni Kurjekar 4 years, 1 month ago

CBSE > Class 10 > Science

5 answers

Komathi .R 4 years, 1 month ago

The sky is blue in day time because scattering of light

0Thank You

Aadarsh Shrivastav 4 years, 1 month ago

Due to the scattering of blue light. The distant of earth from pole is shorter to comparsion from equator. And also the blue and violent light scatter most that's why the sky appears blue in daytime...

0Thank You

Anjali Taehyung 4 years, 1 month ago

0Thank You

Maurya 8970 4 years, 1 month ago

Because blue light is more scattered than other colour

0Thank You

Kanika Chand 4 years, 1 month ago

The sunlight that reaches the earth's atmosphere is scattered in all directions by the gases and dust particles present in the atmosphere So blue light is scattered in all directions by the tiny molecules of air in Earth's atmosphere. This is the reason sky appears blue.

2Thank You

ANSWER

Page 102 of 2763

myCBSEguide

myCBSEguide

Test Generator

CUET Mock Tests

Download myCBSEguide App

All Courses

Other Websites

CBSE Courses

Resources

Corporate

NCERT Solutions

CBSE Sample Papers