MCQs of Dual Nature of Radiation and Matter

Dual Nature of Radiation and Matter MCQs

MCQs of Dual Nature of Radiation and Matter

Showing 31 to 40 out of 186 Questions

31.

Energy of photon is E=hf and its momentum is

p = \frac{h}{λ}

, where

λ

is the wavelength of photon. With this assumption speed of light wave is .....

(a)	$\frac{p}{E}$
(b)	$\frac{E}{p}$
(c)	Ep
(d)	${(\frac{E}{p})}^{2}$

32.

Wavelength

λ_{A}

and

λ_{B}

are incident on two identical metal plates and photo electrons are emitted. if

λ_{A} = 2 λ_{B}

, the maximum kinetic energy of photo electrons is .....

(a)	$2 K_{A} = K_{B}$
(b)	$K_{A} < \frac{K_{B}}{2}$
(c)	$K_{A} = 2 K_{B}$
(d)	$K_{A} > \frac{K_{B}}{2}$

33.

Cathode rays traveling in the direction from east to west enter in an electric field directed from north to south. They will deflect in .....

(a)	east
(b)	west
(c)	south
(d)	north

34.

If photoelectric effect is not seen with the ultraviolet radiation in a given metal, photo electrons may be emitted with the .....

(a)	infrared waves
(b)	radio wave
(c)	X-rays
(d)	visible light

35.

Photon of energy 1 eV and 2.5 eV successively illuminate a metal, whose work function is 0.5 eV, the ratio of maximum speed of emitted electron is .....

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

36.

When frequencies

f_{1}

and

f_{2}

are incident on two identical photo sensitive surfaces, maximum velocities of photo electrons of mass m and

ν_{1}

and

ν_{2}

, hence .....

(a)	${ν_{1}}^{2} - {ν_{2}}^{2} = \frac{2 h}{m} (f_{1} - f_{2})$
(b)	$ν_{1} + ν_{2} = {[\frac{2 h}{m} (f_{1} + f_{2})]}^{\frac{1}{2}}$
(c)	${ν_{1}}^{2} + {ν_{2}}^{2} = \frac{2 h}{m} (f_{1} + f_{2})$
(d)	$ν_{1} - ν_{2} = {[\frac{2 h}{m} (f_{1} + f_{2})]}^{\frac{1}{2}}$

37.

A proton and an

α

-particle are passed through same potential difference. If their initial velocity is zero, the ratio of their de Broglie's wavelength after getting accelerated is .....

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

38.

Mass of photon in motion is .....

(a)	$\frac{c}{hf}$
(b)	$\frac{h}{λ}$
(c)	hf
(d)	$\frac{hf}{c^{2}}$

39.

Wavelength of an electron having energy 10 keV is ..... Å.

(a)	0.12
(b)	1.2
(c)	12
(d)	120

40.

If the momentum of an electron is required to be same as that of wave of 5200Å wavelength, its velocity should be ..... ms^-1 .

(a)	10³
(b)	1.2×10³
(c)	1.4×10³
(d)	2.8×10³

Showing 31 to 40 out of 186 Questions