The radius of a nucleus of a mass number A is directly proportional to [MH CET 1999; AMU (En.) 2001; UPSEAT 2004; DUMET 2010]

(1) A3           (2) A             (3) A2/3             (4) A1/3

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:


The half life of Po218 is 3 minutes. What fraction of a 10 gram sample of Po218, will remain after 15 minutes?

(1) 132         (2) 164            (3) 125            (4) 115

Concept Questions :-

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

Difficulty Level:


mP and mn are masses of proton and neutron respectively. An element of mass m has Z protons and N neutrons, then 

(1) m>Zmp+Nmn

(2) m=Zmp+Nmn

(3) m<Zmp+Nmn

(4) m may be greater than, less than or equal to Zmp+Nmn, depending on the nature of the element.

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:


The nuclei C136 and N147 can be described as [1990]

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

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:


The radioactivity of a sample is A1 at a time t1 and A2 at time t2.  If the mean life of the specimen is T, the number of atoms that have disintegrated in the time interval of t2-t1 is:

(1) A1-A2             (2) A1-A2T               (3) A1-A2T                (4) A1t1-A2t2

Concept Questions :-

Radioactivity
To view Explanation, Please buy any of the course from below.
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) 12 s          (2) 1 s             (3) 38 s             (4) 34 s

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

(1) 2.5×10-11 m

(2) 2.5×10-9 m

(3) 7×10-9 m

(4) 7×10-6 m

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:


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

Difficulty Level:


The ratio of the radii of the nuclei A13l27 and T52e125 is approximately [1990]

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

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:


Bragg's law for X-rays is 

(1) d sin θ= 2 nλ                          (2) 2d sin θ= nλ

(3) n sin θ= 2 λd                          (4) None of these

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

Difficulty Level: