The work function for a certain metal is 4.2eV. Will this metal give photoelectric emission for incident radiation of wavelength 330 nm? Use, \(h=6.6\times { 10 }^{ -34 }Js\)

2

(a)

Ultraviolet light is incident on two photosensitive materials having work function.\({ \phi }_{ 1 }and{ \phi }_{ 2 }\) In which case will the K.E. of the emitted electrons be greater? Why? 

2

(a)

If the wavelength of an electromagnetic radiation is doubled, what will happen to (i) the energy of photons and (ii) the momentum of a photon?

2

(a)

Why is the wave nature of matter not more apparent to our daily observations?

2

(a)

A particle with rest mass is\({ m }_{ 0 }\) moving with velocity c. What is the de-Broglie wavelength associated with it?

2

(a)

An electron and a proton have the same de-Broglie wavelength. Which one these have higher kinetic energy? Which one is moving faster?

2

(a)

The threshold frequency for a certain metal is \(3.3\times { 10 }^{ 14 }Hz\). If light of frequency \(8.2\times { 10 }^{ 14 }Hz\) is incident on the metal, predict the cut-off voltage for the photoelectric emisson.

2

(a)

Why is the wave nature of matter not more apparent to our daily observations?

2

(a)

(i)For what kinetic energy of a neutron will associated de=Broglie wavelength be 1.40X10^-10m?
(ii)Also find the de-Broglie wavelength of a neutron in thermal equilibrium with matter,having an average kinetic energy of (3/2) kT and temperature is 300 K.

2

(a)

Show that the wavelength of electromagnetic radiation is equal to the de-Broglie wavelength of its quantum(Photon).

2

(a)

A proton and a particle have the same de-Broglie wavelength.Determine the ratio of
(i)their accelerating potentials
(ii)their speeds

2

(a)

Write Einstein's photoelectric equation.Explain the terms of stopping potential.

2

(a)

An electron is revolving around the nucleus with a constant speed of 2.2x10⁸ m/s. Find the de Broglie wavelength associated with it.

2

(a)

An \(\alpha \)-particle and a proton are accelerated from rest by the same potential. Find the ratio of their de-broglie wavelengths.

2

(a)

Find the ratio of the de Broglie wavelengths, associated with
(i) protons, accelerated through a potential of 128 V, and
(ii) \(\alpha \)-particles, accelerated through a potential of 64 V.

2

(a)