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A geostationary satellite is orbiting the Earth at a height of 5R above that surface of the Earth, R being the radius of the Earth. The time period of another satellite in hours at a height of 2R from the surface of the Earth is:

  • Option 1)

    5

  • Option 2)

    10

  • Option 3)

    6\sqrt2

  • Option 4)

    \frac{6}{\sqrt2}

 

An electron moving in a circular orbit of radius r makes n rotations per second. The magnetic field produced at the centre has magnitude:

  • Option 1)

    \frac{\mu_0ne}{2\pi r}

  • Option 2)

    \frac{\mu_0n^{2}e}{r}

  • Option 3)

    \frac{\mu_0ne}{2r}

  • Option 4)

    Zero

 

A wire carrying current I has the shape as shown in adjoining figure. Linear parts of the wire are very long and parallel to X-axis while semicircular portion of radius R is lying in Y-Z plane. Magnetic field at point O is :

 

  • Option 1)

    B= \frac{\mu_0 I}{4 \pi R}(\pi \hat{i}+ 2\hat{k})

  • Option 2)

    B= -\frac{\mu_0 I}{4 \pi R}(\pi \hat{i}- 2\hat{k})

  • Option 3)

    B= -\frac{\mu_0 I}{4 \pi R}(\pi \hat{i}+ 2\hat{k})

  • Option 4)

    B= \frac{\mu_0 I}{4 \pi R}(\pi \hat{i}- 2\hat{k})

 

An alternating electric field of frequency v, is applied across the dees (radius = R) of a cyclotron that is being used to accelerate protons (mass = m). The operating magnetic field (B) used in the cyclotron and the kinetic energy (K) of the proton beam produced by it, are given by:

  • Option 1)

    B=\frac{mv}{e}\: \: and\: \: K=2m\pi^{2}\nu^{2} R^{2}

  • Option 2)

    B=\frac{2\pi mv}{e}\: \: and\: \: K=m^{2}\pi\nu R^{2}

  • Option 3)

    B=\frac{2\pi mv}{e}\: \: and\: \: K=2m\pi^{2}\nu^{2} R^{2}

  • Option 4)

    B=\frac{mv}{e}\: \: and\: \: K=m^{2}\pi\nu R^{2}

 

The ratio of the specific heats \frac{C_p}{C_v}= \gamma in terms of degrees of freedom (n)  is given by:

  • Option 1)

    (1+\frac{1}{n})

  • Option 2)

    (1+\frac{n}{3})

  • Option 3)

    (1+\frac{2}{n})

  • Option 4)

    (1+\frac{n}{2})

 

During change of O2 to \text{O}_{2}^{-} ion, the electron adds on which one of the following orbitals?

  • Option 1)

    \pi orbital

  • Option 2)

    \sigma^{*} orbital

  • Option 3)

    \sigma orbital

  • Option 4)

    \pi^{*} orbital

 

Maximum bond angle at nitrogen is present in which of the following ?

  • Option 1)

    NO_2

  • Option 2)

    NO_2^{-}

  • Option 3)

    NO_2^{+}

  • Option 4)

    NO_3^{-}

 

The correct bond order in the following species is:

  • Option 1)

    O_2^{2+}>O_2^{+}>O_2^{-}

  • Option 2)

    O_2^{2+}<O_2^{+}<O_2^{-}

  • Option 3)

    O_2^{2+}>O_2^{+}<O_2^{-}

  • Option 4)

    O_2^{2+}<O_2^{+}>O_2^{-}

 

Typical growth curve in plants is:

  • Option 1)

    Stair-steps shaped

  • Option 2)

    Parabolic

  • Option 3)

    Sigmoid

  • Option 4)

    Linear

 

A certain metallic surface is illuminated with monochromatic light of wavelength, \lambda. The stopping potential for photo-electric current for this light is 3V0. If the same surface is illuminated with light of wavelength 2\lambda, the stopping potential is V0. The threshold wavelength for this surface for photo-electric effect is:

  • Option 1)

    4 \lambda

  • Option 2)

    \frac{\lambda}{4}

  • Option 3)

    \frac{\lambda}{6}

  • Option 4)

    6 \lambda

 

For a reversible process at T=300k, the volume of 2 mole of ideal gas is increased from 1 litre to 10 litres, the \delta H for isothermal change is:

  • Option 1)

    11.47 kJ

  • Option 2)

    4.98 kJ

  • Option 3)

    0

  • Option 4)

    2.49 kJ

 

A  water jet, whose cross-sectional area 'a' strikes a wall making an angle \theta with the normal and rebounds elastically. The velocity of water of density 'd' is v. Force exerted on the wall is : 

  • Option 1)

    2av^{2}d\cos \theta

  • Option 2)

    2av^{2}d\sin \theta

  • Option 3)

    2avd\cos \theta

  • Option 4)

    2avd\sin \theta

 

Radius of the second Bohr orbit of a singly ionised helium atom is

  • Option 1)

    0.53 A \degree

  • Option 2)

    1.06 A \degree

  • Option 3)

    0.265 A \degree

  • Option 4)

    0.132 A \degree

 

A particle of mass m is released from rest and follows a parabolic path as shown. Assuming that the displacement of the mass from the origin is small, which graph correctly depicts the position of the particle as a function of time

  • Option 1)

  • Option 2)

  • Option 3)

  • Option 4)

 

Two particles are oscillating along two close parallel straight lines side by side, with the same frequency and amplitudes. They pass each other, moving in opposite directions when their displacement is half of the amplitude. The mean positions of the two particles lie on a straight line perpendicular to the paths of the two particles. The phase difference is

  • Option 1)

    0

  • Option 2)

    1

  • Option 3)

    \pi

  • Option 4)

    \pi/6

 

if   f(x)+2f\left ( \frac{1}{x} \right )=3x,x\neq 0,  and  S=\left \{ x\, \epsilon \, R : f(x)=f(-x)\right \};then S:

  • Option 1)

    is an empty set.

  • Option 2)

    contains exactly one element.

  • Option 3)

    contains exactly two elements.

  • Option 4)

    contains more than two elements.

 

The graph of the function  y=f\left ( x \right )  is symmetrical about the line x=2 ,then

  • Option 1)

    f\left ( x \right )= f\left ( -x \right )

  • Option 2)

    f\left (2+ x \right )= f\left ( 2-x \right )

  • Option 3)

    f\left ( x +2\right )= f\left ( x-2 \right )

  • Option 4)

    f\left ( x \right )=- f\left ( -x \right )

 

Element with electronic configuration 1s^{2}, 2s^{2}, 2p^{6}, 3s^{2}3p^{6}3d^{10},4s^{2}4p^{6}4d^{10}, 5s^{2}5p^{3} belongs to which group of the periodic table?

  • Option 1)

    3rd

  • Option 2)

    15th

  • Option 3)

    7th

  • Option 4)

    2nd

 

Total number of rotational conformers of n-butane are:

  • Option 1)

    2

  • Option 2)

    6

  • Option 3)

    5

  • Option 4)

    3

 

The energy absorbed in the transition of the electron from n=2 to 1 in H-atom will be 

  • Option 1)

    10.2 meV

  • Option 2)

    3.4 meV

  • Option 3)

    13.6 meV

  • Option 4)

    12.75 meV

 

testing

Need to know specific ways to learn.

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What percent of   \frac{3}{7}  is  \frac{1}{105} .

  • Option 1)

    3.32%

  • Option 2)

    2.22%

  • Option 3)

    45%

  • Option 4)

    450%

  • Option 5)

    10%    

What is the 20% of 50% of 75% of 50% of 140 ?

  • Option 1)

    5.25

  • Option 2)

    4.25

  • Option 3)

    7.25

  • Option 4)

    5.5

  • Option 5)

    6.75

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