MCQs of Nuclei

Nuclei MCQs

Showing 11 to 20 out of 138 Questions

11.

1g radioactive element reduces to 1/3g after 2 days. After total 6 days how much mass will remain ?

(a)	1/27 g
(b)	1/6 g
(c)	1/9 g
(d)	1/12 gBy\;the\;di\sin tegration\;of\;the\;{}_{94}Pu^{241}\;,\;the\;element\;which\;is\;produced\;is\;also\;radioactive\;and\;di\sin tegrates.\;In\;such\;a\;series\;total\;8\;\alpha-particles\;and\;5\;\beta-particles\;are\;emitted\;and\;then\;the\;process\;stops.\;Which\;is\;the\;final\;element\;produced?

12.

B i n d i n g e n e r g y p e r n u c l e o n f o r {}_{z}^{n}P a n d {}_{z'}^{2 n}Q a r e x a n d y r e s p e c t i v e l y . H o w m u c h e n e r g y w o u l d b e a b s o r b e d i n t h e p r o c e s s {}_{z}^{n}P + {}_{z'}^{2 n}P = {}_{z'}^{2 n}Q ?

(a)	2nxy
(b)	2ny + 2nx
(c)	2nx – 2ny
(d)	$\frac{2 n x}{2 n y}$

13.

I f t h e n u m b e r o f u n d i \sin t e g r a t e d n u c l e i a t t i m e t i s g i v e n b y N = N_{0} e^{- λ t}, w h a t i s t h e n u m b e r o f n u c l e i d i \sin t e g r a t e d b e t w e e n t h e t i m e t 1 a n d t 2 ?

(a)	$N_{0} (e^{- λ t_{2}} - e^{- λ t_{1}})$
(b)	$N_{0} (e^{- λ t_{1}} - e^{- λ t_{2}})$
(c)	$N_{0} (e^{λ t_{2}} - e^{λ t_{1}})$
(d)	$N_{0} (e^{λ t_{1}} - e^{λ t_{2}})$

14.

If the half-lives of a radioactive element for α-decay and β-decay are 4 yr and 12 yr respectively, what percent would its total activity be of its initial activity after 12 yrs ?

(a)	50
(b)	25
(c)	12.5
(d)	6.25

15.

Out of Cd, molten Na-metal and graphite which can be used respectively as moderator, coolant and the material for control rods in a reactor?

(a)	Molten Na-metal, graphite, Cd
(b)	graphite, molten Na-metal, Cd
(c)	Cd, molten Na-metal, graphite
(d)	graphite, Cd, molten Na-metal

16.

I f {}_{13}^{27}A l i s s t a b l e n u c l e u s, w h a t c o u l d b e e m i t t e d f r o m {}_{13}^{32}A l n u c l e u s ?

(a)	α-particle
(b)	$β^{-} - p a r t i c l e$
(c)	Proton
(d)	$β^{+} - p a r t i c l e$

17.

The half-life of a radioactive element is 2 hr and that of the other is 4 hr. Their initial activities are equal. After 4 hr what will be the ratio of their activities ?

(a)	1 : 4
(b)	1 : 3
(c)	1 : 2
(d)	1 : 1

18.

1 m o l e o f a n e l e m e n t e m i t t i n g α - p a r t i c l e s i s p l a c e d i n a v e s s e l w h i c h s t o r e s t h e m . H a l f - l i f e o f t h a t e l e m e n t i s 5 h r . H o w l o n g w o u l d i t t a k e f o r 4.515 \times 10^{23} α - P a r t i c l e s t o b e s t o r e d i n t h a t v e s s e l ?

(a)	4.515 hr
(b)	9.030 hr1\;mole\;of\;an\;element\;emitting\;\alpha-particles\;is\;placed\;in\;a\;vessel\;which\;stores\;them.\;Half-life\;of\;that\;element\;is\;5\;hr.\;How\;long\;would\;it\;take\;for\;4.515\;\times\;10^{23}\;\alpha-Particles\;to\;be\;stored\;in\;that\;vessel?
(c)	10 hr
(d)	20 hr

19.

I n t h e r a d i o a c t i v e t r a n s f o r m a t i o n {}_{Z}^{A}X \to {}_{Z + 1}^{A}X_{1} \to {}_{Z - 1}^{A - 4}X_{2} \to {}_{Z}^{A - 4}X_{3}, w h i c h a r e t h e s u c c e s s i v e l y e m i t t e d r a d i o a c t i v e r a d i a t i o n s ?

(a)	$α, β^{-}, β^{-}$
(b)	$β^{-}, α, β^{-}$
(c)	$β^{-}, β^{-}, α$
(d)	$α, α, β^{-}$

20.

I n t h e r a d i o a c t i v e t r a n s f o r m a t i o n X \overset{α}{\to} X_{1} \overset{β^{-}}{\to} X_{2} \overset{β^{-}}{\to} X_{3} w h i c h t w o a r e t h e i s o t o p e s ?

(a)	$X a n d X_{1}$
(b)	$X a n d X_{3}$
(c)	$X_{1} a n d X_{2}$
(d)	$X_{2} a n d X_{3}$

Showing 11 to 20 out of 138 Questions