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Name the multicelled sterile hairs present between antheridium?

Posted by Saba Elias 6 years, 11 months ago

CBSE > Class 11 > Biology

1 answers

Ʌɐpɐʎ Ɐuɐɥsɹɐp . 6 years, 11 months ago

yarr one word may clean bold ker re hoo.. ?... paraphyses is the answer..

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ANSWER

Who is the father of indian pteridology? And who gave the term pterodophyta?

Posted by Saba Elias 6 years, 11 months ago

CBSE > Class 11 > Biology

1 answers

Ʌɐpɐʎ Ɐuɐɥsɹɐp . 6 years, 11 months ago

S. s bir is the father of Indian pteridology... nd I think linnaeus gave the term... not sure about second one.. ?

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Calculate the critical angle for glass air interface, if a ray of light incidence in air on the surface is deviated through 15° when its angle of incidence is 40°. (Hr. Board 2009)

Posted by Saba Elias 6 years, 11 months ago

CBSE > Class 11 > Physics

3 answers

Ankit Singh 6 years, 11 months ago

Nice Answer Nancy

1Thank You

Nancy Rajput 6 years, 11 months ago

=>critical angle be ic. =>sinic= 1/ u where u is the refractive index of glass. => sin i / sin r =u i = 40° =>r = 40 - 15 = 25° => u = sin 40 / sin 25 => u = 1.521 = >sinic= 1/ 1.521 => ic=> sin-1(0.657) =41.11°

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Nancy Rajput 6 years, 11 months ago

41.11o

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ANSWER

What is optical fibres?

Posted by Saba Elias 6 years, 11 months ago

CBSE > Class 11 > Physics

2 answers

Ankit Singh 6 years, 11 months ago

An optical fiber is a thin fiber of glass or plastic that can carry light from one end to the other. The study of optical fibers is called fiber optics, which is part of applied science and engineering. Optical fibres have become very important in high-speed communications, such as cable TV and high-speed broadband services. Information, in the form of pulses of light, is sent down bundles of optical fibres. Fibre optic cables are able to carry more signals than traditional copper cable telephone lines. Hope this will help u saba ??

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Nancy Rajput 6 years, 11 months ago

Optical fibers are made of glass. These are glass fibers. Now for fiber optic communication glass fibers are simply not enough they have to be specially built for total internal reflection (TIR). To achieve TIR the optical fiber is given an outer layer having a lower refractive index called cladding and the central part of the glass fibre is called core.

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Mohan sold machiney on credit prepare a journal entry

Posted by Shivam Agrawal 6 years, 11 months ago

CBSE > Class 11 > Accountancy

2 answers

Sakshi Sharma ??️??️??️ 6 years, 11 months ago

Debtor's A/c. Dr To machinery A/c

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Aditya Jain 6 years, 11 months ago

Mohan Account dr. To Machinery Account

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20 tranctions with journal entries , ledger ,and trial balance

Posted by Kasturi Devi 6 years, 11 months ago

CBSE > Class 11 > Accountancy

0 answers

ANSWER

Explain variable and manipulating methods and their types?

Posted by Khushi Kumari 6 years, 11 months ago

CBSE > Class 11 > Informatics Practices

0 answers

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A point source of light is place 4 m below the surface of water of refractive index 5/3 . The minimum diameter of disc which should be placed over the source on the surface of water to cut off all light coming out of water is ( mu=5/3)

Posted by Saba Elias 6 years, 11 months ago

CBSE > Class 11 > Physics

6 answers

Ʌɐpɐʎ Ɐuɐɥsɹɐp . 6 years, 11 months ago

tnx.. ?✌️

2Thank You

Ankit Singh 6 years, 11 months ago

Nice answer darshana

1Thank You

Ʌɐpɐʎ Ɐuɐɥsɹɐp . 6 years, 11 months ago

OK then,, here it is ⤵️ ➡️ sin i = 1/μ = 3/5.......... ➡️tan i = 3/4= r/4.. by solving this we get radius = 3 m.... now we know that diameter =2×radius.. so,,,, diameter =2×3=6m....hope you understand.. ✌️

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Saba Elias 6 years, 11 months ago

Yah... its right give me the full solution

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Ʌɐpɐʎ Ɐuɐɥsɹɐp . 6 years, 11 months ago

if it is correct then I can give full solution of it..

1Thank You

Ʌɐpɐʎ Ɐuɐɥsɹɐp . 6 years, 11 months ago

answer may be 6m...

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Blue print for final exam

Posted by Dr.Ekta Joshi 6 years, 11 months ago

CBSE > Class 11 > Chemistry

1 answers

Mridhula Sri 6 years, 11 months ago

It will differ for each and every school

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ANSWER

The function f is defined by f(x).Draw the graph of f(x).

Posted by Rishav Verma 6 years, 11 months ago

CBSE > Class 11 > Mathematics

0 answers

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Limits and derivatives derivations

Posted by Ravikumar Ml 6 years, 11 months ago

CBSE > Class 11 > Mathematics

2 answers

Ankit Singh 6 years, 11 months ago

Which derivation

3Thank You

Nancy Rajput 6 years, 11 months ago

which

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if the satellite is stopped suddenly in its orbit and allowed to fell freely on to the earth. Find the speed with which it hits the surface of the earth.

Posted by Yatin Singh 6 years, 11 months ago

CBSE > Class 11 > Physics

6 answers

Nishita Tomar 6 years, 11 months ago

this app is updated according to new syllabus..

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Aman Kumar 6 years, 11 months ago

Wo toh hum jante hai...bus thoda likhne wale k muhh se sunna chahte the...

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Ʌɐpɐʎ Ɐuɐɥsɹɐp . 6 years, 11 months ago

sub Google ki den hai... ?? itna v ni samjhte... ???

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Aman Kumar 6 years, 11 months ago

And haan update this app according to new syllabus...??

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Aman Kumar 6 years, 11 months ago

Gaurav ji...etna lamba answer laate kaha se hai app..???

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Gaurav Seth 6 years, 11 months ago

The question is incomplete.

Q. A satellite is moving Only a circular orbit around the earth Again a height 6400km if the satellite Is suddelny stopped in its orbit and allowed to fall freely towards earth find the speed with which it hits the surface of the earth.

<hr />

Ans.

Height of the satellite from the surface of Earth = H = 6400 km.
Radius of Earth = R = 6400 km.
Mass of Earth = M.
G = Universal Gravitational constant.

Initial KE = 0. Speed = 0.
Gravitational potential energy of the satellite at height 6400 km
PE1 = - G M m/(H+R) = - G M m/ (2R)
= - (G M/R²) * (mR/2)
= - m g R / 2 , as gravity g on Earth's surface = GM/R²

This potential energy on the surface of Earth:
PE2 = - GMm/R = - (GM/R²) × (mR)
= - m g R

Potential Energy lost = PE1 - PE2
ΔPE = m g R/2

Kinetic energy gained = ΔKE = 1/2 m v²
1/2 m v² = m g R/2
v² = g R
v = √[g R]
= √[9.81 × 6400,000] m/s
v = 7923.64 m/s. = 28, 525 km/hr

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Plz give answer of question no 12 of practical problem chapter no 19

Posted by Nanu Sekhon 6 years, 11 months ago

CBSE > Class 11 > Accountancy

2 answers

D J 6 years, 11 months ago

of which book ?

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Sakshi Sharma ??️??️??️ 6 years, 11 months ago

Kon se book se

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What is storyline of Mothers day byJB Priestly

Posted by Littleshine Aaaru?? 6 years, 11 months ago

CBSE > Class 11 > English Core

2 answers

Gaurav Seth 6 years, 11 months ago

This humorous and satirical depiction of a mother's status in a family was written way back in 1950 and till date stands quite true in cases of house wives. Unless and until she fights back for her rights her contribution is not recognized in the family. The characters in this play are Mrs. Annie Pearson (the mother); husband Mr. George Pearson., son Cyril, daughter Doris and the neighbor Mrs. Fitzgerald. Mrs. Fitzgerald knows tarot card reading which she had learnt while she was living in the east with her husband. She finds out that Mrs. Pearson does not get the due respect she should get from her family and advices her to take strong steps to be the mistress of her own house . Though Mrs. Pearson doubted herself if she will be able to follow her advice. She didn't want any unpleasantness in her house .More over she didn't know when or how to put her point.Mrs Fitzgerald advised her to start that very day but Mrs. Pearson was reluctant as she won't be able to keep her promise. Mrs. Fitzgerald had an excellent idea. As she had learnt many magic in the east, she can change place with Mrs. Pearson i.e.Mrs. Pearson will have Mrs. Fitzgerald's mind and vice versa. They both held hands and sat on the table quietly. Mrs. Fitzgerald enchanted some magic words and their minds got exchanged. After Mrs. Fitzgerald with Mrs. Pearson's mind leaves for her house Doris arrives and sees s her mother smoking. She is shocked. She has an argument with her as now all of a sudden her mother is not ready to iron her dresses for the evening or prepare tea or even supper.Dorris was horrified at her mother's attitude and runs away crying. After sometime Cyril appears from work and he too is flatly denied when he asks for tea. Cyril was alarmed and asks if she was feeling well or not? Then Mrs. Pearson takes out a bottle of stout and drinks. Both the siblings are astonished and start wondering if she has had a fall or hit her head. Now Mr. Person arrive and all three start complaining about tea not being ready as they had worked so hard for eight hours. to this Mrs. Pearson says that from that very moment she would also work for only eight hours a day and weekends off.Mr Pearson gets angry and get ready for club when Mrs. Pearson tell him that people at the club call him Pompy Ompy Pearson and laughs at him. He becomes very sad. Now Mrs. Fitzgerald with Mrs. Pearson's mind enters the house and seeing everyone sad asks to leave Mrs. Pearson and her alone for a few minutes and may be everything will be all right. On being alone Mrs. Fitzgerald enchants some magic words and again their bodies get back their mind but now Mrs. Pearson's family give her more respect and considers her likes and dislikes also.

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Littleshine Aaaru?? 6 years, 11 months ago

Plzz it is important

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Which is the best option for starting up a business firm?

Posted by Parag Patra 6 years, 11 months ago

CBSE > Class 11 > Entrepreneurship

0 answers

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a cosA+b cosC+c cosC=2a sinB sinC

Posted by Kartik Bhai 6 years, 11 months ago

CBSE > Class 11 > Mathematics

0 answers

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What is a viscosity?

Posted by Piyush Kumar Pradhan 6 years, 11 months ago

CBSE > Class 11 > Physics

3 answers

Nancy Rajput 6 years, 11 months ago

Viscosity is the measure of internal friction of a liquid.This friction arises between different layers of a liquid and offers resistance to the flow of the liquid.Greater is the friction, greater is the amount of force required to cause the movement of liquid.Highly viscous fluids have more fraiction than less viscous fluids.The SI units of viscosity are Kg/ms or Pa s.

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Archit Singh 6 years, 11 months ago

Molecular force of attraction between the molecules of a fluid

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Gaurav Seth 6 years, 11 months ago

Viscosity refers to the resistance to the flow of liquid arising as a result of the internal friction within the layers as they pass over other layer.

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How many moles are there in 6g of mg?

Posted by Atharv Negi 6 years, 11 months ago

CBSE > Class 11 > Chemistry

3 answers

Ankit Singh 6 years, 11 months ago

0.24686 moles

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Nancy Rajput 6 years, 11 months ago

moles

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Nancy Rajput 6 years, 11 months ago

its 0 .24686

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Sample paper

Posted by Rajender Kumar 6 years, 11 months ago

CBSE > Class 11 > Accountancy

0 answers

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How physical and natural science related

Posted by Ichha Thapa 6 years, 11 months ago

CBSE > Class 11 > Geography

0 answers

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Why lif is insolube but licl is soluble in water

Posted by K. J 6 years, 11 months ago

CBSE > Class 11 > Chemistry

5 answers

Ankit Singh 6 years, 11 months ago

Nice answer Nancy and ayushi

1Thank You

Ayushi Ayushi 6 years, 11 months ago

LiF is almost insoluble in water due to high lattice energy. But LiCl is soluble in water due to high hydration energy of Li+ ion. ... covalent character increases when increases the size of anion , that's why LiCl is soluble in acetone ( covalent compound ) but LiF is insoluble in acetone .

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Nancy Rajput 6 years, 11 months ago

hopes it help you

1Thank You

Nancy Rajput 6 years, 11 months ago

LiF is insoluble in water. On the contrary, LiCl is soluble not only in water, but also in acetone. Reason: This is mainly because of the greater ionic character of LiF as compared to LiCl. The solubility of a compound in water depends on the balance between lattice energy and hydration energy. Since fluoride ion is much smaller in size than chloride ion, the lattice energy of LiF is greater than that of LiCl. Also, there is not much difference between the hydration energies of fluoride ion and chloride ion. Thus, the net energy change during the dissolution of LiCl in water is more exothermic than that during the dissolution of LiF in water. Hence, low lattice energy and greater covalent character are the factors making LiCl soluble not only in water, but also in acetone.

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K. J 6 years, 11 months ago

Have high lattice enthalpy

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The sum of the roots of the equation axpower2+x+c=0 is equal to the sum of the reciprocal of their squares. a,capower2,cpower2 are in which? AP GP HP

Posted by Anshul Kumar 6 years, 11 months ago

CBSE > Class 11 > Mathematics