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Engineering
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Engineering
6 days, 7 hours ago
Confused! kindly explain, - Complex numbers and quadratic equations - JEE Main-13

Let \alpha and \beta   be the roots of equation

x^{2}-6x-2=0.\; if a_{n}=\alpha ^{n}-\beta ^{n},\; for\: n\geq 1,\; then\; the \: value\; of\; \frac{a_{10}-2a_{8}}{2a_{9}}

is equal to:

  • Option 1)

    6

  • Option 2)

    -6

  • Option 3)

    3

  • Option 4)

    -3

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S solutionqc
Answered 5 days, 7 hours ago
\(\\x^2-6x-2=0\\\alpha+\beta=6\\\alpha\cdot\beta=-2\\Given,\;\;\frac{a_{10}-2a_8}{2a_9},\;\;where\;\;a_n=\alpha^n-\beta^n\\\Rightarrow \frac{a_{10}-2a_8}{2a_9}=\frac{\alpha ^{10}-\beta ^{10}-2\left(\alpha \:^8-\beta \:^8\right)}{2\left(\alpha \:^9-\beta \:^9\right)}\\replace\;\;-2\;\;with\;\;\alpha\beta\\\Rightarrow \frac{\alpha ^{10}-\beta ^{10}+\left(\alpha \beta \right)\left(\alpha ^8-\beta...
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Engineering
3 weeks, 6 days ago
Solve it, Compound X will be

Compound X will be 

  • Option 1)

  • Option 2)

  • Option 3)

  • Option 4)

 

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S solutionqc
Answered 3 weeks, 5 days ago
    Hydrolysis of acyl halides and anhydrides - Acid chlorides on hydrolysis give carboxylate ion which on acidification yield carboxylic acid. Anhydrides hydrolysed to the corresponding acid. - wherein       Option 1) Option 2) Option 3) Option 4)
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Engineering
4 weeks ago
Try this! - Organic Compounds containing Oxygen - JEE Main

Find the compound "X" which give the following test:

Neutral FeCl3  -Ve

Fehling Solution  -ve

Iodoform reaction  +ve

Grignard reagent  +ve

 

  • Option 1)

  • Option 2)

  • Option 3)

  • Option 4)

 

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S solutionqc
Answered 3 weeks, 6 days ago
Option 1) Option 2) Option 3) Option 4)
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Engineering
4 weeks ago
Help me solve this Two particles move at right angle to each other de Broglie wavelengths as and , particle suffers a perfectly inelastic collision. The de Broglie wavelength of final particle is given by

Two particles move at right angle to each other de Broglie wavelengths as \lambda_1 and \lambda_2, particle suffers a perfectly inelastic collision. The de Broglie wavelength \lambda of final particle is given by

  • Option 1)

    \lambda=\frac{\lambda _{1}\lambda _{2}}{\sqrt{\lambda_{1}^{2}+\lambda_{2}^{2}}}

  • Option 2)

    \lambda=2\frac{\lambda _{1}\lambda _{2}}{\sqrt{\lambda_{1}^{2}+\lambda_{2}^{2}}}

  • Option 3)

    \lambda=\frac{\lambda _{1}^2\lambda _{2}}{\sqrt{\lambda_{1}^{2}+\lambda_{2}^{2}}}

  • Option 4)

    \lambda=\frac{\lambda _{1}\lambda _{2}}{2\sqrt{\lambda_{1}^{2}+\lambda_{2}^{2}}}

 

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R rachana cm
Answered 3 weeks, 6 days ago

option 3

 

Engineering
4 weeks ago
Help me please, An interference experiment ratio of amplitude of coherent waves is . What is the ratio of maximum and minimum intensities of frings?

An interference experiment ratio of amplitude of coherent waves is . What is the ratio of maximum and minimum intensities of frings?

  • Option 1)

    1

  • Option 2)

    2

  • Option 3)

    3

  • Option 4)

    4

 

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P Plabita
Answered 3 weeks, 6 days ago
Option 1) 1 Option 2) 2 Option 3) 3 Option 4) 4
Engineering
4 weeks ago
Help me understand! What is time at which the rate of dissipation is equal to the rate at which magnetic energy stored in the inductor?

What is time at which the rate of dissipation is equal to the rate at which magnetic energy stored in the inductor?

  • Option 1)

    1.4 sec

  • Option 2)

    1.9 sec

  • Option 3)

    5 sec

  • Option 4)

    0.03 sec

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M Mothi ramkrishna
Answered 3 weeks, 6 days ago

option 3

 

Engineering
4 weeks ago
I have a doubt, kindly clarify. Plane electromagnetic wave travelled in x-direction has electric field component E = 6V/m which is in y-direction. Corresponding Magnetic field component (B) is-

Plane electromagnetic wave travelled in x-direction has electric field component E = 6V/m which is in y-direction. Corresponding Magnetic field component (B) is-

  • Option 1)

    B_0=2*10^{-8}T (in \ \ z-axis)

  • Option 2)

    B_0=6*10^{-8}T (in \ \ z-axis)

  • Option 3)

    B_0=12*10^{-8}T (in \ \ z-axis)

  • Option 4)

    B_0=2*10^{8}T (in \ \ z-axis)

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A aadil.khan
Answered 3 weeks, 6 days ago
Option 1)Option 2)Option 3)Option 4)
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Engineering
4 weeks ago
Help me understand! Bob at pendulum mass 2g, charge , an electric field of intensity 2000v/m. Angle of pendulum with vertical at equilibrium?

Bob at pendulum mass 2g, charge , an electric field of intensity 2000v/m. Angle of pendulum with vertical at equilibrium?

  • Option 1)

    \Theta = tan^{-1}{\frac{1}{2}}

  • Option 2)

    \Theta = cot^{-1}{\frac{1}{2}}

  • Option 3)

    \Theta = sin^{-1}{\frac{1}{2}}

  • Option 4)

    \Theta = tan^{-1}{\frac{1}{4}}

 

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P Plabita
Answered 3 weeks, 6 days ago
Option 1) Option 2) Option 3) Option 4)
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Engineering
4 weeks ago
Help me answer: Consider a Steel wire of radius= 2mm of a load equal to 4 kg to be suspended from a rigid support and its top end, such that it is in hanging in a vertical position. What is its tensile stress due to its own weight? (take )

Consider a Steel wire of radius= 2mm of a load equal to 4 kg to be suspended from a rigid support and its top end, such that it is in hanging in a vertical position. What is its tensile stress due to its own weight? (take g=3.1 \pi ms^{-2} )

  • Option 1)

    6.2*10^{6} Nm^2

  • Option 2)

    3.1*10^{-6} Nm^2

  • Option 3)

    3.1*10^{6} Nm^2

  • Option 4)

    3.1*10^{5} Nm^2

 

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P Plabita
Answered 3 weeks, 6 days ago
Option 1) Option 2) Option 3) Option 4)
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Engineering
4 weeks ago
Help me understand! If gas molecules each of mass Kg collide over the area of in unit second with Speed , the pressure exerted will be?

If   gas molecules each of mass Kg collide over the area of   in unit second with  Speed , the pressure exerted will be?

  • Option 1)

    3Nm^{2}

  • Option 2)

    2 \ Nm^2

  • Option 3)

    4Nm^{2}

  • Option 4)

    6Nm^{2}

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P Plabita
Answered 3 weeks, 6 days ago
Option 1)Option 2)Option 3)Option 4)
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Engineering
4 weeks ago
I have a doubt, kindly clarify. In SI units, the dimension of is

In SI units, the dimension of is

  • Option 1)

  • Option 2)

    M^{-1}L^{2}T^{3}A

  • Option 3)

    M^{-1}L^{2}T^{5}A^{2}

  • Option 4)

    M^{-1}L^{2}T^{-3}A

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P Plabita
Answered 3 weeks, 6 days ago
Option 1)Option 2)Option 3)Option 4)
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Engineering
4 weeks, 1 day ago
Solve it, The major product formed in the reaction given below will be:

The major product formed in the reaction given below will be:

  • Option 1)

  • Option 2)

  • Option 3)

  • Option 4)

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P Plabita
Answered 4 weeks ago
  Fate of aliphatic diazonium ion - The diazonium ions of aliphatic amines are very unstable and produces carbocation immediately, which can produce different products.  - wherein      Fate of aromatic diazonium ion - Diazonium salts of aromatic amines are comparatively more stable and evolve nitrogen only on heating.These diazonium salts can be isolated at low temperatures. -             As...
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Engineering
4 weeks, 1 day ago
Can someone help me with this, If in a parallelogram ABDC, the coordinates of A,B and C are respectively (1,2), (3,4) and (2,5) , then the equation of the diagonal AD is:

If in a parallelogram ABDC, the coordinates of A,B and C are respectively (1,2), (3,4) and (2,5) , then the equation of the diagonal AD is:

  • Option 1)

    5x-3y+1=0

  • Option 2)

    3x-5y+1=0

  • Option 3)

    5x+3y-11=0

  • Option 4)

    3x+5y-13=0

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P Plabita
Answered 4 weeks ago
  Mid-point formula -   - wherein If the point P(x,y) is the mid point of line joining A(x1,y1) and B(x2,y2) .     Two – point form of a straight line -   - wherein The lines passes through    and    As BD and AC are parallel ..............................(1) As AB and CD are parallel ..............................(2) Solving (1) and (2) m=4 and n=7              Option 1)Option 2)Option...
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Engineering
4 weeks, 1 day ago
Stuck here, help me understand: - Some basic concepts in chemistry - JEE Main-2

50 mL of 0.5 M oxalic acid is needed to neutralize 25 mL of sodium hydroxide solution. The amount of NaOH in 50 mL of the given sodium hydroxide solution is :

  • Option 1)

    20 g

  • Option 2)

    4 g

  • Option 3)

    10 g

  • Option 4)

    40 g

 

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P Plabita
Answered 4 weeks ago
  Molar Mass - The mass of one mole of a substance in grams is called its molar mass. - wherein  Molar mass of water = 18 g mol-1       Molarity -  Molarity (M) = (Number of moles of solute)/(volume of solution in litres)   - wherein It is defined as the number of moles of the solute in 1 litre of the solution.       Stoichiometry - Stoichiometry deals with measurements of reactants and...
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Engineering
4 weeks, 1 day ago
Help me solve this - p- Block Elements - JEE Main

Match the catalysts (Column I) with products (Column II).

             ColumnI                                          Column II

            Catalyst                                               Product

      (A)   V_{2}O_{5}                                          (i) Polyethylene     

      (B)  TiCl_{4}/Al(Me)_{3}                      (ii) ethanal

      (C)   PdCl_{2}                                       (iii)   H_{2}SO_{4}

      (D) Iron\; Oxide                               (iv)   NH_{3}

 

 

  • Option 1)

     (A)-(iii); (B)-(iv);(C)-(i);(D)-(ii)

  • Option 2)

      (A)-(ii);(B)-(iii);(C)-(i);(D)-(iv)

  • Option 3)

     (A)-(iii);(B)-(i);(C)-(ii);(D)-(iv)

  • Option 4)

     (A)-(iv);(B)-(iii);(C)-(ii);(D)-(i)

 

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S solutionqc
Answered 4 weeks ago
      Contact Process - In this process SO2 obtained by burning of S or iron pyrites which is catalytically oxidised to  in presence of timely divided Pt or  as catalyst -       High density Polythene (HDP) - -  Polymerization of ethene in a hydrocarbon solvent under low pressure in presence of triethylaluminium and titanium tetrachloride (Ziegier. natta catalyst) -  Chain growth,...
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Engineering
4 weeks, 1 day ago
Please,please help me - Some Basic Principles of Organic Chemistry - JEE Main-2

The increasing order of nucleophilicity of the following nucleophilies is :

(a)\; CH_{3}CO_{2}^{\ominus }

(b)\; H_{2}O

(c)\; CH_{3}SO_{3}^{\ominus }

(d)\;\overset{\ominus }{O}H

  • Option 1)

    (a)< (d)< (c)< (b)

  • Option 2)

     (b)< (c)< (d)< (a)

  • Option 3)

     (d)< (a)< (c)< (b)

  • Option 4)

    (b)< (c)< (a)< (d)

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V Vakul
Answered 4 weeks ago
    Nucleophile - Those e- rich  chemical species having capacity to attack e-deficient portion of substrate. - wherein Nucleophile must have complete octet and atleast one lone pair                      Order of Nucleophilicity is                                                                                                                                                   Both are...
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Engineering
4 weeks, 1 day ago
Confused! kindly explain, The correct option among the following is :

The correct option among the following is :

  • Option 1)

    Colloidal medicines are more effective because they have small surface area.

  • Option 2)

    Addition of alum to water makes it unfit for drinking .

  • Option 3)

    Colloidal particles in lyophobic sols can be precipitated by electrophoresis.

  • Option 4)

     Brownian motion in colloidal solution is faster if the viscosity of the solution is very high.

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P Plabita
Answered 4 weeks ago
    Properties of Colloidal Solutions - Coagulation or Precipitation - wherein The stability of the lyophobic sols is due to the presence of charge on colloidal particles. If somehow the charge is removed the particles will come nearer to each other and settle down under gravity.       Properties of Colloidal Solutions - Electrophoresis - wherein The existance of charge on colloidal...
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Engineering
4 weeks, 1 day ago
Please,please help me Benzene diazonium chloride on reaction with aniline in the presence of dilute hydrochloric acid gives:

Benzene diazonium chloride on reaction with aniline in the presence of dilute hydrochloric acid gives:

 

  • Option 1)

  • Option 2)

  • Option 3)

  • Option 4)

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V Vakul
Answered 4 weeks ago
    Coupling reaction of aromatic diazonium - Diazonium ions of aromatic amines also undergo coupling reaction with aromatic rings having a strong activating group to form diazo compounds. - wherein      Option 1)Option 2)Option 3)Option 4)
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Engineering
4 weeks, 1 day ago
Confused! kindly explain, The metal that gives hydrogen gas upon treatment with both acid as well as base is :

The metal that gives hydrogen gas upon treatment with both acid as well as base is :

  • Option 1)

    zinc

  • Option 2)

    iron

  • Option 3)

    mercury

  • Option 4)

    magnesium

 

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S solutionqc
Answered 4 weeks ago
    Oxidation states - Transition elements have a variety of oxidation states but the common oxidation state is +2 for 3d metals.   -     zinc is the metal that gives hydrogen gas on reacting with both acid & base (i)  (ii)  Option (I) is correct Option 1) zinc Option 2) iron Option 3) mercury Option 4) magnesium
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Engineering
4 weeks, 1 day ago
Can someone explain The major product of the following reaction is-2

The major product of the following reaction is 

 

  • Option 1)

  • Option 2)

  • Option 3)

  • Option 4)

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V Vakul
Answered 4 weeks ago
  Side chain chlorination followed by hydrolysis - The halogenation/chlorination of Toluene can occur in 2 methods of electrophilic substitution: The Chlorine either substitutes itself with a Hydrogen atom in the phenyl ring, or it substitutes with a Hydrogen atom in the Methyl group (side chain reaction) to form variants of Chloromethylbenzene/Benzyl Chloride (C6H5CH2Cl).   Electrophilic...
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