Dual Nature of Radiation and Matter

In photoelectric effect an em-wave is incident on a metal surface and electrons are ejected from the surface. If the work function of the metal is 2.14 eV and stopping potential is 2 V, what is the wavelength of the em-wave? (Given hc=1242 eV nm where h is the Planck's constant and c is the speed of light in vacuum.)

1. 400 nm
2. 600 nm
3. 300 nm
4. 200 nm

The work functions of cesium (Cs) and lithium (Li) metals are 1.9 eV and 2.5 eV , respectively. If we incident a light of wavelength 550 nm on these two metal surfaces, then photo-electric effect is possible for the case of

1. Both Cs and Li
2. Neither Cs nor Li
3. Li only
4. Cs only

A light source of wavelength illuminates a metal surface and electrons are ejected with maximum kinetic energy of 2 eV . If the same surface is illuminated by a light source of wavelength 2, then the maximum kinetic energy of ejected electrons will be (The work function of metal is 1 eV )

1. 5 eV
2. 3 eV
3. 2 eV
4. 6 eV

A proton, an electron and an alpha particle have the same energies. Their de-Broglie wavelengths will be compared as :

1. p > e >
2. < p < e
3. e > > p
4. p < e <

UV light of 4.13 eV is incident on a photosensitive metal surface having work function 3.13 eV. The maximum kinetic energy of ejected photoelectrons will be:

1. 4.13 eV
2. 1 eV
3. 7.26 eV
4. 3.13 eV

A proton and an electron are associated with same de-Broglie wavelength. The ratio of their kinetic energies is: (Assume h = 6.63 10-34 J s, me = 9.0 10-31 kg and mp = 1836 times me)

1. 1 : 11836
2. 1 : 1836
3. 1 : 1836
4. 1 : 1 1836

A proton and an electron have the same de Broglie wavelength. If Kp and Ke be the kinetic energies of proton and electron respectively, then choose the correct relation :

1. Kp > Ke
2. Kp = Ke
3. Kp < Ke
4. Kp = Ke2

Which of the following phenomena is not explained by wave nature of light? Choose the most appropriate answer from the options given below:

1. C only
2. B, D only
3. A, C only
4. E only

In photoelectric experiment energy of 2.48 eV irradiates a photo sensitive material. The stopping potential was measured to be 0.5 V. Work function of the photo sensitive material is :

1. 1.98 eV
2. 1.68 eV
3. 2.48 eV
4. 0.5 eV

When UV light of wavelength 300 nm is incident on the metal surface having work function 2.13 eV, electron emission takes place. The stopping potential is : (Given hc = 1240 eV nm)

1. 4 V
2. 2 V
3. 4.1 V
4. 1.5 V