NEET 2017 | Dual Nature of Radiation and Matter Question 16 | Physics

NEET 2017

MCQ (Single Correct Answer)

-1

The de-Broglie wavelength of a neutron in thermal equilibrium with heavy water at a temperature T (kelvin) and mass m, is

$${h \over {\sqrt {3mkT} }}$$

$${{2h} \over {\sqrt 3 mkT}}$$

$${{2h} \over {\sqrt {mkT} }}$$

$${h \over {\sqrt {mkT} }}$$

NEET 2016 Phase 2

MCQ (Single Correct Answer)

-1

Photons with energy 5 eV are incifent on a cathode C in a photoelectric cell. The maximum energy of emitted photoelectrons is 2 eV. When photons of energy 6 eV are incident on C, no photoelectrons will reach the anode A, if the stopping potential of A relative to C is

+ 3 V

+4 V

$$-$$1 V

$$-$$3 V

NEET 2016 Phase 2

MCQ (Single Correct Answer)

-1

Electrons of mass m with de-Broglie wavelength $$\lambda $$ fall on the target in an X-ray tube. The cutoff wavelength ($$\lambda $$₀) of the emitted X-ray is

$$\lambda $$₀ = $${{2mc{\lambda ^2}} \over h}$$

$${\lambda _0} = {{2h} \over {mc}}$$

$${\lambda _0} = {{2{m^2}{c^2}{\lambda ^3}} \over {{h^2}}}$$

$${\lambda _0} = \lambda $$

NEET 2016 Phase 1

MCQ (Single Correct Answer)

-1

When a metallic surface is illuminated with radiation of wavelength $$\lambda $$, the stopping potential is V. If the same surface is illuminated with radiation of wavelength 2 $$\lambda $$, the stopping potential is $${V \over 4}$$. The threshold wavelength for the metallic surface is

$${5 \over 2}\lambda $$

3$$\lambda $$

4$$\lambda $$

5$$\lambda $$

PREVIOUS NEXT

NEET Subjects

Biology

Botany

Zoology

Human Health and Diseases Body Fluids and Its Circulation Locomotion and Movement Neural Control and Coordination Reproduction in Organisms Reproductive Health Structural Organisation in Animals Digestion and Absorption Excretory Products and Their Elimination Chemical Coordination and Integration Human Reproduction Animal Kingdom Breathing and Exchange of Gases Evolution