MCQs of Dual Nature of Radiation and Matter

Dual Nature of Radiation and Matter MCQs

MCQs of Dual Nature of Radiation and Matter

Showing 151 to 160 out of 186 Questions

151.

In a photo-electric effect measurement, the stopping potential for a given metal is found to be

V_{0}

vvolt, when radiation of wavelength

λ_{0}

is used.If radiation of

2 λ_{0}

is used with the same metal, then the stopping potential in volt will be _____ .

(a)	$\frac{V_{0}}{2}$
(b)	$2 V_{0}$
(c)	$V_{0} + \frac{h c}{2 e λ_{0}}$
(d)	$V_{0} - \frac{h c}{2 e λ_{0}}$

152.

The work function for tungsten and sodium are 4.5 eV and 2.3 eV respectively. If the threshold wavelength λ₀ for sodium is 5460 Å, the value of λ₀ for tungsten is _____ Å .

(a)	2791
(b)	528
(c)	5893
(d)	10683

153.

A metal surface of work function 1.07 eV is irradiated with light of wavelength 330 nm. The resting potential required to stop the escape of photo electrons is _____ V.

(a)	1.07
(b)	2.69
(c)	3.74
(d)	4.81

154.

A particle of mass m kg and charge q coulomb is accelerated through V volt, then the de Broglie wavelength associated with it, in meter is

λ

= _____ m.

(a)	$λ = \frac{h}{mV}$
(b)	$λ = \frac{h}{\sqrt{mqV}}$
(c)	$λ = \frac{h}{\sqrt{2 Vmq}}$
(d)	$λ = \frac{h}{\sqrt{2 mV}}$

155.

What should be the velocity of an electron so that its momentum become equal to that of a photon of wavelength 5200 Å ?

(a)	10³ ms^-1
(b)	1.3×10³ ms^-1
(c)	1.4×10³ ms^-1
(d)	2.8×10³ ms^-1

156.

If a proton and electron have same de Broglie wavelength, then _____ .

(a)	both have same kinetic energies
(b)	proton has more K.E. than electron
(c)	electron has more K.E. than proton
(d)	both have same velocity.

157.

If the mass of neutron is 1.7×10^-27 kg , then the de Broglie wavelength of neutron of energy of 3 eV is _____ . (h=6.6×10^-34 J.sec)

(a)	1.6×10^-10 m
(b)	1.63×10^-11 m
(c)	1.4×10^-10 m
(d)	1.4×10^-11 m

158.

What wavelength is corresponding to a beam of electrons whose kinetic energy is 100 eV? (h=6.6×10^-34 J.sec ,1 eV=1.6×10^-19 J , m_e=9.1×10^-31 kg )

(a)	1.2 Å
(b)	2.4 Å
(c)	3.6 Å
(d)	4.8 Å

159.

K_{1}

and

K_{2}

are maximum K.E. of photo-electron emitted when light of wavelength

λ_{1}

and

λ_{2}

respectively incident on a metallic surface. If

λ_{1} = 3 λ_{2}

, then _____ .

(a)	$K_{1} > \frac{K_{2}}{3}$
(b)	$K_{1} < \frac{K_{2}}{3}$
(c)	$K_{1} = 3 K_{2}$
(d)	$K_{2} = 3 K_{1}$

160.

If the uncertainty in the position of proton is 6×10^-8 m , then the maximum uncertainty in its speed will be _____ .

(a)	1 em/sec
(b)	1 ms^-1
(c)	1 mm/sec
(d)	100 mm/sec

Showing 151 to 160 out of 186 Questions