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If f-1 exist if f is

A) one to one function

B) surjective

C) bijective

D) into

Posted by Saurabh Tharu (Jun 25, 2017 9:43 p.m.) (Question ID: 6180)

• The answer is option A and B

Answered by Soumya Rai (Jun 25, 2017 10:24 p.m.)
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1. The maximum value of 10x-5x2-1 is

Posted by KONDA THIRUMALA RAO (Jun 25, 2017 6:48 a.m.) (Question ID: 6162)

• 4

Answered by Payal Singh (Jun 25, 2017 9:48 p.m.)
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Why Vagina's acidity is important?

Posted by Sahil Nilay (Jun 17, 2017 10:07 a.m.) (Question ID: 5971)

• As soon as the vaginal pH value is increased above the value of 4.5, bad bacteria take the opportunity to develop and grow, eventually causing an infection. This can result in symptoms such as discharge, odor, itching and other vaginal discomforts. Changes in pH value are often connected to bacterial vaginosis.

Answered by DR PATHIKRT BANERJEE (Jun 23, 2017 11:01 a.m.)
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Hello . My doubt is that I want solution ( How to solve it , step-by-step)  of the following Question :  " if (Alpha)+(Beta)=3 and (Alpha)(Cube)+(Beta)(Cube)=7 , then (Alpha) and (Beta) are roots of equation "........................ .I hope that you  would reply me soon .

Posted by abhinav ambatipudi (Jun 14, 2017 6:44 p.m.) (Question ID: 5905)

A train passes an electric post in 10 sec. and a bridge of length 2km. in 110 second. what is the speed of the engine?

Posted by Ramesh kumar Tiwari (Jun 13, 2017 11:38 a.m.) (Question ID: 5883)

• Ans. Let Length of Train = x meter

Time taken to cover post = 10 sec

if a train pass post. it mean it is covering distance equal to its length

So speed = {tex}{distance \over time } = {x\over 10} \ .... (1){/tex}

Again if it pass a bridge it cover distance equal to sum of length of bridge and length of train.
Length of Bridge = 2 Km = 2000 m

So distance covered =  ( 2000 + x ) m
Time taken = 110 sec
So Speed = {tex}{2000+x\over 110 } \ ........... (2){/tex}

From (1) and (2), we get

{tex}=> {x\over 10}={2000+x\over 110}{/tex}

=> 110 x = 20000 + 10 x

=> 100x = 20000

=> x = {tex}{20000\over 100} = 200 \ m/s{/tex}

Answered by Naveen Sharma (Jun 13, 2017 3:30 p.m.)
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Give a proper explanation that why tennis ball bounces higher on hills. than in plains

Posted by Amit Thakur (Jun 10, 2017 6:49 a.m.) (Question ID: 5812)

• As from the equation of motions for free fall we have

v2-u2=-2gh     ( at peak point v = 0)

therefore,   -u2 = -2hg

h = u2/2g

As from the above equation h is inversely proportional to g and g on mountains is less from the surface

hence tennis ball bounces more on the mountains than on the plains.

Answered by lalit gautam (Jun 10, 2017 7:48 a.m.)
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The molecule of SO2 is four times heavier than that of CH4. Find root mean square velocity of CH4 molecule.

Posted by Harjot Kaur (Jun 05, 2017 1:43 p.m.) (Question ID: 5690)

• As Vrms=√3RT/√m

V1/V2=√m2/√m1

=√m2/√4m2

=1/2

Answered by Nimesh Ahuja (Jun 06, 2017 7:25 a.m.)
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A carnot engine working between 400k and 800k has a  work output of 1200 joule per cycle what is the amount of heat energy supplied to the engine from the source per cycle

Posted by ROHIT PORIA (Jun 01, 2017 4:31 p.m.) (Question ID: 5621)

• First find efficiency of engine = 1- lower temperature/higher temperature = 1/2 then amount of heat energy is two times of work done = 2400 joule

Answered by Gaurav Bhardwaj (Jun 02, 2017 10:29 p.m.)
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What is rumination simple way

Posted by Maan Wala (Jun 01, 2017 4:07 p.m.) (Question ID: 5617)

• Rumination is the process by which the cow regurgitates previously consumed feed and masticates it a second time. The ruminant stomach has four compartments: rumen, reticulum, omasum, and abomasum.

Answered by Payal Singh (Jun 01, 2017 4:13 p.m.)
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Two element A of atomic weight 75 and B of atomic weight 16 combine two yield a product the percentage by weight of A in the compound was found to be 75.08 the formula of compound is

Posted by Pulkit Bajpai (May 26, 2017 11:10 p.m.) (Question ID: 5513)

•  Element Percentage by weight Atomic weight Relative no. of atoms Simple ratio A 75.8 75 75.8/75 = 1.01 2 B 24.2 16 24.2/16= 1.51 3

Therefore the formula of the compound is A2B3.

Answered by Payal Singh (May 27, 2017 7:37 p.m.)
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8 gram of sulphur are burnt to form a SO2 which is oxidised by CL2  water the solution is treated with bacl2 solution the amount of baso4 precipitated is

Posted by Pulkit Bajpai (May 26, 2017 11:08 p.m.) (Question ID: 5512)

• {tex}S+O_2 \to SO_2 \xrightarrow{Cl/H_2O} H_2SO_4 \xrightarrow{BaCl_2} BaSO_4{/tex}

From the above reaction

1mole of S produces 1 mole of BaSO4 Number of moles in 8g of S = 8/32 = 0.25 Thus number of moles of BaSO= 0.25

Answered by Payal Singh (May 27, 2017 7:42 p.m.)
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2 moles of mixture of co and co2 requires exactly 56 gram KoH in the solution for complete conversion of all the co2 into K2co3. How much amount more of koh will be required for conversion into k2co3 if 2 moles of mixture is completely oxidized to co2?

A 28g

B 56g

C 168g

D 112g

Posted by Pulkit Bajpai (May 26, 2017 10:46 p.m.) (Question ID: 5510)

The volume of chlorine at STP required to liberate all the bromine and Iodine present in 1 mole of KI and 2 moles of MBR2 is ?

A 22.4

B 56

C 44.8

D 33.6

Posted by Pulkit Bajpai (May 26, 2017 10:42 p.m.) (Question ID: 5509)

4 gm of carbon is heated with 8 gm of sulphur .how much cs2 will be formed when the reaction is complete . What will be the % purity?

A 70.2%

B 79.2%

C 90%

D 90.2%

Posted by Pulkit Bajpai (May 26, 2017 10:38 p.m.) (Question ID: 5508)

• B. 79.2%

{tex}C + 2S \to CS_2{/tex}

Ideally, 1 mole of C will react with 2 moles of S to form CS2

1 mol of C = 12g 1 mol of S = 32g

12g carbon reacts with = 64g of Sulphur 1g carbon reacts with = {tex}64\over 12{/tex}g of Sulphur

4g carbon reacts with = {tex}{64\over 12}\times 4 = {64\over 3}{/tex}g of Sulphur

But we have only 8g of sulphur

It mean sulphur is limiting agent.

due to sulphur is limiting reagent reaction will proceed according to sulphur .

64g sulphur formed = 76g CS2

1g S formed=  {tex}76\over 64{/tex} g CS2

8g S formed = {tex}{76\over 64 }\times 8 = 9.5{/tex}g CS2

Hence, % purity {tex}= {Wt. \ of \ product \over Wt. \ of \ reactants } \times 100{/tex}{tex} {9.5 \over (4+8)}\times 100 ={ 9.5\over 12}\times 100 {/tex}

= 79.16 % = 79.2 %

Answered by Payal Singh (May 27, 2017 9:44 p.m.)
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Suppose evolution on earth has occured in such a way that 96 amino acids instead of 20 .DNA has 12 difrnt types of bases nd DNA synthesis occur in same way as today .the min.no.of bases per DNA codon would be??

Posted by Sonia Yadav (May 26, 2017 3:57 p.m.) (Question ID: 5504)

• The min.no.of bases per DNA codon would be Two (2)

Answered by Payal Singh (May 26, 2017 5:22 p.m.)
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• Molality  of NaOH is 1.25,percent by weight of NaOH  is.......
• The only  primary  alcohol that can be prepared by the indirect hydration of alkene is.....
Posted by MUDASSIR MOHIUDDIN INAMDAR (May 24, 2017 4:36 p.m.) (Question ID: 5470)

• The only primary alcohol that can be prepared by the indirect hydration of alkene is ethyl alcohol
Answered by Payal Singh (May 24, 2017 5:32 p.m.)
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• DNA-ase and RNA-ase are enzymes produced by....
• In case of taking food rich in lime juice, the action of ptylin on starch is.....
•  Fatty acids and glycerol are first absorbed by........
Posted by MUDASSIR MOHIUDDIN INAMDAR (May 24, 2017 2:06 p.m.) (Question ID: 5462)

• DNA-ase and RNA-ase are enzymes produced by Pancreas.
• In case of taking food rich in lime juice, the action of ptylin on starch is reduced
• Fatty acids and glycerol are first absorbed by lacteal
Answered by Payal Singh (May 24, 2017 2:23 p.m.)
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Question 1-the resultant of two vectors of magnitude p and 2P is perpendicular to the first <a href="https://www.embibe.com/learn/mathematics/chapter-vector-412">vector</a>. find the <a href="https://www.embibe.com/learn/physics/concept-angle-9428">angle</a> between the resultant and second vector

Question 2 - A cart is  with moving East speed 1 metre per second A man is walking on this cart with a velocity 2 metre per second  with respect to the cart while he moves he swings his left hand with a speed 4 metre per second due West with respect to him. a fly sitting on the man's hand moves with a velocity 6 metre per second due South with respect to the hand  .find the velocity of the fly as seen by a ground observer

Question 3 -As the angle between two forces of fixed magnitude is varied the greatest and the least value of resultant of two forces are 20 Newtons and 10 Newtons respectively. find the magnitude of the forces

Posted by Shankhaneel Ghosh (May 15, 2017 9:14 a.m.) (Question ID: 5313)

• Epinasty in flooded plants is due to.......
• synthetic hormone connected with cell expantion is....
• wavelength of light absorbed by Pr form of phytochrome is.....
Posted by MUDASSIR MOHIUDDIN INAMDAR (May 07, 2017 1:13 a.m.) (Question ID: 5144)

• Epinasty is caused by ethylene that is released by the leaves when the roots are flooded.
• gibberellin
• The Pr form of phytochrome receives red light (600-680 nm) and changes into Pfr.
Answered by Payal Singh (May 07, 2017 10:42 p.m.)
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consider the reaction given below. this reaction will be the fastest in......

CH2CH2CH2Br + NaCl-----> CH3CH2CH2CN + NaBr

Posted by Raima Rakshit (May 05, 2017 9:34 p.m.) (Question ID: 5128)

• This reaction occurs fastest in

N,N'-dimethylformamide (DMF).

Answered by Payal Singh (May 06, 2017 12:05 p.m.)
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• the function of anhydrous AlCl3 in the friedel craft's reaction is to ?
• VSEPR NOTATION OF CHLORINE TRIFLUORIDE MOLECULE IS?
• WHAT IS THE TOTAL NOUMBER OF ATOMS PRESENT IN 25.0mg OF CAMPHOR C10H16
Posted by MUDASSIR MOHIUDDIN INAMDAR (May 05, 2017 12:45 a.m.) (Question ID: 5123)

• Solution:

• To Produce electrophile
• VESPR Notation of ClF3 is AX3E2. AX3E2 has To shaped shape.
Answered by Payal Singh (May 05, 2017 2:53 p.m.)
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1. the maximum probability of finding electron in the dxy orbital is?
Posted by MUDASSIR MOHIUDDIN INAMDAR (May 04, 2017 7:56 p.m.) (Question ID: 5116)

• Give me the answer of question as early

as possible

Posted by MUDASSIR MOHIUDDIN INAMDAR (May 04, 2017 9:25 p.m.)
• The lobes of dxy orbital are oriented in between the axes at an angle 45, So the  probability of finding electron in a dxy orbital is maximum at an angle of 45 degree from x and y axis.

Answered by Payal Singh (May 04, 2017 11:22 p.m.)
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Consider the ground state of Cr atom the number of electrons with the azimuthal quatum numbers l=1 and 2 are respectively? .........provide best concept material for atomic structure! !!

Posted by doreamon superman (Mar 28, 2017 9:22 a.m.) (Question ID: 4560)

1) what is meant by green revolution and blue revolution?

2) Co (or )co2 which one of them is not a green house gas ?

Posted by doreamon superman (Mar 27, 2017 3:48 p.m.) (Question ID: 4550)

• The Green Revolution was a period when the productivity of global agriculture increased drastically as a result of new advances. During this time period, new chemical fertilizers and synthetic herbicides and pesticides were created. The chemical fertilizers made it possible to supply crops with extra nutrients and, therefore, increase yield.

The term "blue revolution" refers to the remarkable emergence of aquaculture as an important and highly productive agricultural activity. Aquaculture refers to all forms of active culturing of aquatic animals and plants, occurring in marine,or fresh waters.

Carbon monoxide (CO) is only a very weak directgreenhouse gas, but has important indirect effects on global warming. Carbon monoxide reacts with hydroxyl (OH) radicals in the atmosphere, reducing their abundance. So, carbon monoxide is not a green house gas.

Answered by Shweta Gulati (Mar 27, 2017 9:23 p.m.)
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Difference between epimers and annomers?

Posted by doreamon superman (Mar 27, 2017 7:58 a.m.) (Question ID: 4542)

• Ans.

• Epimers are monosaccharides that differ in chirality at only one carbon.
• Anomers are special epimers; in cyclic forms of one single monosaccharide.
Answered by Naveen Sharma (Mar 27, 2017 10:06 a.m.)
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