The counting rate observed from a radio active source at t = 0 second was 1600 counts per second and at t = 8 seconds it was 100 counts per second. The counting rate observed, as counts per second, at t = 6 seconds will be

(1) 400         (2) 300         (3) 200        (4) 150

Concept Questions :-

Radioactivity
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:


If N0 is the original mass of the substance of half life period T1/2= 5 years, then the amount of substance left after 15 years is [AIEEE 2012]

(1) N0/8           (2) N0/16           (3) N0/2            (4) N0/4

Concept Questions :-

Radioactivity
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:


The numbers of nuclei of a radioactive substance at time t = 0 are 1000 and 900 at time t = 2 s. Then number of nuclei at time t = 4 s will be

(1) 800            (2) 810             (3) 790             (4) 700

Concept Questions :-

Radioactivity
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:


A nucleus XZA has mass represented by m(A, Z). If mp and mn denote the mass of proton and neutron respectively and BE the binding energy (in MeV), then [2007]

(1) BE = [m(A, Z) - Zmp- (A - Z)mnc2

(2) BE = [Zmp+ (A - Z)mn- m(A,Z)] c2

(3) BE = [Zmp+ Amn- m(A, Z)] c2

(4) BE = m(A, Z) - Zmp- (A, Z)mn

Concept Questions :-

Nuclear binding energy
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:


The equation XAZYAZ+1 + e0-1+ν¯ is          (UP CPMT 2002)

(1) β-emission                (2) α-emission

(3) e- capture                (4) fission

Concept Questions :-

Types of decay
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:


Half-lives of two radioactive substances A and B respectively 20 min and 40 min.  Initially, the samples of A and B have equal number of nuclei. After 80 min the ratio of remaining number of A and B nuclei is [1998]

(1) 1 : 16                         (2) 4 : 1

(3) 1 : 4                           (4) 1 : 1

Concept Questions :-

Radioactivity
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:


Radioactive C2760o is transformed into stable N2860i by emitting two γ-rays of energies [Kerala PET 2010]

(1) 1.33 MeV and 1.17 MeV in succession

(2) 1.17 MeV and 1.33 MeV in succession

(3) 1.37 MeV and 1.13 MeV in succession

(4) 1.17 MeV and 1.13 MeV in succession

Concept Questions :-

Radioactivity
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:


The volume occupied by an atom is greater than the volume of the nucleus by factor of about [2003]

(1) 1010                (2) 1015                (3) 101                (4) 105

Concept Questions :-

Mass-energy equivalent
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:


A radioactive nucleus undergoes a series of decay according to the scheme 

AαA1βA2αA3γA4

If the mass number and atomic number of A are 180 and 72 respectively, then what are these number for A4?

(1) 172 and 69                         (2) 174 and 70

(3) 176 and 69                         (4) 176 and 70

Concept Questions :-

Radioactivity
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:


What fraction of a radioactive material will get disintegrated in a period of two half-lives. 

 

(1) whole                (2) half                (3) one-fourth                (4) three-fourth

Concept Questions :-

Radioactivity
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level: