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Engineering
1 week ago

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 6 days, 21 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...
Engineering
4 weeks, 1 day ago

Compound X will be 

  • Option 1)

  • Option 2)

  • Option 3)

  • Option 4)

 

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S solutionqc
Answered 4 weeks 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)
Engineering
4 weeks, 1 day ago

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 4 weeks ago
Option 1) Option 2) Option 3) Option 4)
Engineering
4 weeks, 1 day ago

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 4 weeks ago

option 3

 

Engineering
4 weeks, 1 day ago

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 4 weeks ago
Option 1) 1 Option 2) 2 Option 3) 3 Option 4) 4
Engineering
4 weeks, 1 day ago

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 4 weeks ago

option 3

 

Engineering
4 weeks, 1 day ago

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 4 weeks ago
Option 1)Option 2)Option 3)Option 4)
Engineering
4 weeks, 1 day ago

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 4 weeks ago
Option 1) Option 2) Option 3) Option 4)
Engineering
4 weeks, 1 day ago

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 4 weeks ago
Option 1) Option 2) Option 3) Option 4)
Engineering
4 weeks, 1 day ago

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 4 weeks ago
Option 1)Option 2)Option 3)Option 4)
Engineering
4 weeks, 1 day ago

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 4 weeks ago
Option 1)Option 2)Option 3)Option 4)
Engineering
1 month ago

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, 1 day 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...
Engineering
1 month ago

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, 1 day 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...
Engineering
1 month ago

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, 1 day 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...
Engineering
1 month ago

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, 1 day 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,...
Engineering
1 month ago

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, 1 day 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...
Engineering
1 month ago

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, 1 day 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...
Engineering
1 month ago

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, 1 day 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)
Engineering
1 month ago

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, 1 day 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
Engineering
1 month ago

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, 1 day 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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