The nuclei  can be described as [1990]

(1) isotones        (2) isobars          (3) isotopes of carbon           (4) isotopes of nitrogen

Concept Questions :-

Mass-energy equivalent
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The radioactivity of a sample is ${A}_{1}$ at a time ${t}_{1}$ and ${A}_{2}$ at time ${t}_{2}$.  If the mean life of the specimen is T, the number of atoms that have disintegrated in the time interval of ${t}_{2}-{t}_{1}$ is:

(1) ${A}_{1}-{A}_{2}$             (2) $\frac{{A}_{1}-{A}_{2}}{T}$               (3) $\left({A}_{1}-{A}_{2}\right)T$                (4) ${A}_{1}{t}_{1}-{A}_{2}{t}_{2}$

Concept Questions :-

High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

Three fourth of the active nuclei decay in a radioactive sample in 3/4 s. The half-life of the sample is

(1)           (2) 1 s             (3)              (4)

Concept Questions :-

High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

What is the radius of iodine atom? (atomic no. 53, mass no. 126) [1988]

(1)

(2)

(3)

(4)

Concept Questions :-

Mass-energy equivalent
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

Which of the following statements is true for nuclear forces? [1990]

(1) They obey the inverse square law of distance.

(2) They obey the inverse third power law of distance.

(3) They are short range forces.

(4) They are equal in strength to electromagnetic forces.

Concept Questions :-

Mass-energy equivalent
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The ratio of the radii of the nuclei ${}_{13}A{l}^{27}$ and ${}_{52}T{e}^{125}$ is approximately [1990]

(1) 6 : 10               (2) 13 : 52              (3) 40 : 177                (4) 14 : 73

Concept Questions :-

Mass-energy equivalent
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

Bragg's law for X-rays is

(1) d sin $\theta$= 2 n$\lambda$                          (2) 2d sin $\theta$= n$\lambda$

(3) n sin $\theta$= 2 $\lambda$d                          (4) None of these

High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The relationship between disintegration constant $\left[\lambda \right]$ and half-life [T] will be:

(1)                     (2)

(3)                       (4)

Concept Questions :-

High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

Alpha particles are

(1) 2 free protons

(2) helium atoms

(3) singly ionized helium atoms

(4) doubly ionised helium atoms

Concept Questions :-

Mass-energy equivalent
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

A radioactive sample with a half-life of 1 month has the label: 'Activity = 2 microcurie on 1-8-1991'. What would be its activity two months earlier?

(1) 1.0 microcurie

(2) 0.5 microcurie

(3) 4 microcurie

(4) 8 microcurie

Concept Questions :-