Assertion: The photoelectrons produced by a monochromatic light beam incident on a metal
surface, have a spread in their kinetic energies. 

Reason: The work function of the metal varies as a function of depth from the surface.

• If both assertion and reason are true and reason is the correct explanation of the assertion

• If both assertion and reason are true but reason is not the correct explanation of the assertion

• If assertion is true, but reason is false

• Both assertion and reason are false statements

Assertion: The energy (E) and momentum (p) of a phoon are related by p = E/c.

Reason: the photon behaves like a particle.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false

A leaf which contains only green pigments is illuminated by a  laser light of wavelength  0.6328 μm. It would appear to be

• brown

• black

• red

• green

A photon of energy 4 eV is incident on a metal surface whose work function is 2 eV. The minimum reverse potential to be applied for stopping the emission of electrons is

• 2 V

• 4 V

• 6 V

• 8 V

We wish to see inside an atom. Assuming the atom to have a diameter of  100 pm, this means that one must be able to resolve a width of say 10 pm. If an electron microscope is used, the minimum electron energy required is about

• 1.5 keV

• 15 keV

• 150 keV

• 1.5 keV

Assertion:  A red object appears dark in the yellow light.

Reason: The red colour is scattered less.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false

Assertion:  Photoelectric effect demonstrates the wave nature of light.

Reason: The number of photoelectrons is proportional to the frequency of light

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false

168.

If an electron and a photon propagate in the form of waves having the same wavelength, it implies that they have the same

• energy

• momentum

• velocity

• angular momentum

Characteristic X-rays are produced due to

• transfer of momentum in collision of electrons with target atoms

• transition of electron from higher to lower electrons orbits in an atom

• heating of the target

• transfer of energy in collision of electrons with atoms in the target

Assertion:  A tube light emits white light. 

Reason: Emission of light in a tube takes place at a very high temperature.

• if both assertion and reason are true and the reason is the correct explanation of the assertion

• if both assertion and reason are true and the reason is not the correct explanation of the assertion

• if assertion is true but reason is false

• if both assertion and reason are false statements