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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

3

Compound X will be 

  • Option 1)

  • Option 2)

  • Option 3)

  • Option 4)

 

2

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)

 

1

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}}}

 

option 3

 

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

 
Option 1) 1 Option 2) 2 Option 3) 3 Option 4) 4

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

option 3

 

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)

Option 1)Option 2)Option 3)Option 4)

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}}

 
Option 1) Option 2) Option 3) Option 4)

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

 
Option 1) Option 2) Option 3) Option 4)