MCQs of Dual Nature of Radiation and Matter

Dual Nature of Radiation and Matter MCQs

MCQs of Dual Nature of Radiation and Matter

Showing 81 to 90 out of 186 Questions

81.

A photosensitive metallic surface has work function Φ. If photon of energy 3Φ fall on this surface, the electron comes out with a maximum velocity of 6×10⁶ m/s . When the photon energy is increased to 9Φ, then maximum velocity of photoelectron will be _____ .

(a)	12×10⁶ m/s
(b)	6×10⁶ m/s
(c)	3×10⁶ m/s
(d)	24×10⁶ m/s

82.

An electron and a proton are moving in the same direction with same kinetic energy. The ratio of the de Broglie wavelength associated with these particle is _____ .

(a)	$\frac{m_{e}}{m_{p}}$
(b)	$\frac{m_{p}}{m_{e}}$
(c)	$\sqrt{\frac{m_{p}}{m_{e}}}$
(d)	$m_{p \cdot} m_{e}$

83.

The work function of a metal is 1.6 eV. What is the maximum wavelength of light that can produce photoelectric emission from the metal ? (h=6.6×10^-34 Js , 1eV=1.6×10^-19 J , c=3×10⁸ ms^-1)

(a)	29000Å
(b)	3867Å
(c)	7734Å
(d)	5800Å

84.

Which of the following has longest de Broglie wavelength, if they move with same velocity ?

(a)	α-particle
(b)	Proton
(c)	β-particle
(d)	Neutron

85.

The work function of a substance is 4.0 eV. The longest wevelength of light that can cause photo electric emission from this substance is approximately _____

(a)	310 nm
(b)	400nm
(c)	540nm
(d)	220nm

86.

If the kinetic energy of free electron is made double, the new de Broglie wavelength will be _____ times, that of initial wavelength.

(a)	$\sqrt{2}$
(b)	2
(c)	$\frac{1}{\sqrt{2}}$
(d)	$\frac{1}{2}$

87.

Threshold wavelength for lithium metal is 6250 Å. For photo emission, the wavelength of the incident light must be _____ .

(a)	more than 6250 Å
(b)	equal to or more than 6250 Å
(c)	exactly equal to 6250 Å
(d)	equal to or les than 6250 Å

88.

A body of mass 100 g moves at the speed of 36 km/hr. The de Broglie wavelength related o it is of the order _____ m. (h=6.6×10^-34 Js )

(a)	10^-14
(b)	10^-34
(c)	10^-24
(d)	10^-44

89.

de Broglie wavelength of atom at T K absolute temperature will be _____ .

(a)	$\frac{h}{m k T}$
(b)	$\frac{\sqrt{2 m k T}}{h}$
(c)	$\frac{h}{\sqrt{3 m k T}}$
(d)	$\sqrt{2 m k T}$

90.

Photons having energy 1 eV and 2.5 eV successively incident on a metal, having work function is 0.5 eV. The ratio of maximum speed of emitted electrons is _____ .

(a)	1:2
(b)	3:1
(c)	2:1
(d)	1:3

Showing 81 to 90 out of 186 Questions