The energy of a photon of wavelength l = 1 meter is (Planck's constant = 6.626 $\times$ ${10}^{-34}$ Js, speed of light $=<mspace\; width="1em"></mspace>3<mspace\; width="1em"></mspace>\times <mspace\; width="1em"></mspace>{10}^5<mspace\; width="1em"></mspace>\mathrm{m}/\mathrm{s}$)

1.  1.988 x ${10}^{-25}<mspace\; width="1em"></mspace>\mathrm{J}$

2.  1.988 x ${10}^{-32}<mspace\; width="1em"></mspace>\mathrm{J}$

3.  1.988 x ${10}^{-28}<mspace\; width="1em"></mspace>\mathrm{J}$

4.  1.988 x ${10}^{-38}<mspace\; width="1em"></mspace>\mathrm{J}$

For a one-electron atom, the set of allowed quantum numbers is

1.  n = 1, l = 0, ${\mathrm{m}}_{\mathrm{l}}$ = 0, ${\mathrm{m}}_s$ = +1/2

2.  n = 1, l = 1, ${\mathrm{m}}_{\mathrm{l}}$ = 0, ${\mathrm{m}}_s$ = +1/2

3.  n = 1, l = 0, ${\mathrm{m}}_{\mathrm{l}}$ = -1, ${\mathrm{m}}_s$ = -1/2

4.  n = 1, l = 0, ${\mathrm{m}}_{\mathrm{l}}$ = 1, ${\mathrm{m}}_s$ = -1/2

A metal is irradiated with light of wavelength 660 nm. Given that the work function of the metal is I .0 eV. the de-Broglie wavelength of the ejected electron is close to

1.  6.6 x ${10}^{-7}$ m

2.  1.3 x ${10}^{-9}$ m

3.  8.9 x ${10}^{-11}$ m

4.  6.6 x ${10}^{-13}$ m

The energy of an electron in the first Bohr orbit is

1.  -30.6 eV

2.  -40.8 eV

3.  -54.4 eV

4.  +40.8 eV

When a certain metal was irradiated with light of frequency 3.2 x ${10}^{16}$ Hz, the photoelectrons emitted had twice the kinetic energy as did the photoelectrons emitted when the same metal Was irradiated with light of frequency 2.0 x ${10}^{16}$Hz The $v_0$ of the metal is

1.  2.4 x ${10}^{16}$ Hz

2.  8.0 x ${10}^{16}$Hz

3.  8.0 x ${10}^{15}$ Hz

4.  7.2 x ${10}^{16}$Hz

An electron beam can undergo diffraction by crystals which proves the wave nature Of electrons. The potential required for a beam Of electrons to be accelerated so that its wavelength becomes equal to 0.154 nm is

1.  63.5 V

2.  31.75 V

3.  635 V

4.  127 V

Which of the given graphs depicts the correct relation between the kinetic energy of photoelectrons and the frequency of incident light (v)?

1.          2.  

3.           4.  

The total number of electron present in Cu Which have zero value of magnetic quantum number in the ground state

1. 13

2. 7

3. 8

4. 15

Spin multiplicity of Ca $\left(1s^2<mspace\; width="1em"></mspace>2s^2<mspace\; width="1em"></mspace>2p^{6}3s^{2}3p^{6}4s^2\right)$ in ground state is 

1.  1 only

2.  2 only 

3.  Either 3 or 1

4.  3 only 

Of the following transitions in hydrogen atom, the one which gives an absorption line of lowest frequency is:

1.  n = 1 to n = 2

2.  n = 3 to n = 8

3.  n = 2 to n = 1

4.  n = 8 to n = 3