MCQs of Nuclei

Nuclei MCQs

Showing 61 to 70 out of 138 Questions

61.

A nucleus with Z = 92 emits the following in a sequence : α, α, β^-, β^-, α, α, α, α, β^-, β^-, α, β⁺, β⁺, α. The Z of the resulting nucleus is _____ .

(a)	78
(b)	82
(c)	74
(d)	76

62.

A nucleus disintegrates into two nuclear parts which have their velocities in the ratio of 2 : 1. The ratio of their nuclear sizes will be _____ .

(a)	$3^{\frac{1}{2}} : 1$
(b)	$1 : 2^{\frac{1}{3}}$
(c)	$2^{\frac{1}{3}} : 1$
(d)	$1 : 3^{\frac{1}{2}}$

63.

The intensity of gamma radiation from a given source is I . On passing through 36 mm of lead, it is reduced to \frac{1}{8} . The thickness of lead which will reduce the intensity to \frac{1}{2} will be____.

(a)	6 mm
(b)	9 mm
(c)	18 mm
(d)	12 mm

64.

Half-lives of two radioactive elements A and B are 20 minutes and 40 minutes, respectively. Initially, the samples have equal number of nuclei. After 80 minutes the ratio of decayed numbers of A and B nuclei will be _____ .

(a)	1 : 16
(b)	4 : 1
(c)	1 : 4
(d)	5 : 4

65.

Which of the following is true for the value of \frac{N}{Z} for the nuclei of heavy elements which are found stable ?

(a)	< 1
(b)	= 1
(c)	> 1 but < 2
(d)	> 2

66.

Of which physical quantity is 'fermi' the unit ?

(a)	Length
(b)	Energy
(c)	Mass
(d)	Time

67.

Of which physical quantity is "curie (Ci)" the unit ?

(a)	Decay constant
(b)	Binding energy
(c)	Half-life
(d)	Activity

68.

What is the ratio approximately of the mass of α-particle and the mass of proton ?

(a)	4
(b)	2
(c)	8
(d)	6

69.

What is the ratio of the charge of α-particle and the charge of proton ?

(a)	4
(b)	2
(c)	3
(d)	6

70.

Energy of each of α-particle, β-particle and γ-radiation is 0.5 MeV. Arrange them in the ascending order of their penetrating power. (i.e., take the one with minimum value as first)

(a)	α, β, γ
(b)	α, γ, β
(c)	γ, β, α
(d)	β, γ, α

Showing 61 to 70 out of 138 Questions