A radioactive material has half life of 10 days . What fraction of materials would be remain after 30 ? A ) 1 / 4 , B ) 1 / 8 , C ) 1 / 12 , D ) None of these ,

1 ) A radioactive material has half life of 10 days . What fraction of materials would be remain after 30 ?

A ) 1 / 4 ,                                          B ) 1 / 8 ,

C ) 1 / 12 ,                                               D ) None of these ,

Correct Answer : -  B ) 1 / 8 ,

solution : -

 

2 ) The half life of a radioactive substance is 10 days . This means that : -

A ) 1/8 parts of mass , if the substance will be left intact at the end of 40 days .

B ) 7/8 part of mass of substance disintegrates in 30 days .

Correct Answer : -  B ) 7/8 part of mass of substance disintegrates in 30 days .

Solution : -

 

3 ) A certain radioactive element has half life of 4 days . The fraction of material that decays in 2 days ?

A )  ( √2 – 1 ) / √2  ,                          B )  ( 1 - √2 ) / √2  ,

C )  1 / √2  ,                                      D ) None of these ,

Correct Answer : -  A ) ( √2 – 1 ) / √2  ,

Solution : -

 

4 )  In a transistor , if  ( α = IC / IE    and    β = IC / IB )   α – varies between 20/21 and 100/101 , Then value of β lies between : -

A ) 20 – 101 ,                                           B ) 20 – 100 ,

C ) 21 – 101 ,                                          D ) None of these ,

Correct Answer : - B ) 20 – 100 ,

Solution : -

 

5 ) A Geiger counter ( Geiger - Muller tube ) is a device used for detection and measurement of ......... radiations .

A ) alpha ,                                                B ) beta ,

C ) gamma ,                                            D ) All of these ,

Correct Answer : -  D ) All of these ,

 

6 ) Typical source of beta - particle is .............  ( Strontium – 90 ) .

Now go to online quiz section and Physics Quiz 8 is uploaded related to these mcqs  , so check your preparation by this link : -

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