Home
Class 12
PHYSICS
M(x) and M(y) denote the atomic masses o...

`M_(x) and M_(y)` denote the atomic masses of the parent and the daughter nuclei respectively in a radioactive decay. The Q - value for a `beta-` decay is `Q_(1)` and that for a `beta^(+)` decay is `Q_(2)`. If `m_(e)` denotes the mass of an electrons, then which of the following statements is correct?

A

`Q_(1) = (M_(x) -M_(y))c^(2)` and `Q_(2) =(M_(x)-M_(y) -2m_(e))c^(2)`

B

`Q_(1)-(M_(x)-M_(y))c^(2)` and `Q_(2)=(M_(x)-M_(y))c^(2)`

C

`Q_(1)=(M_(x)-M_(y) -2m_(e))c^(2)` and `Q_(2)=(M_(x)-M_(y) + 2m_(e))c^(2)`

D

`Q_(1) =(M_(x) -M_(y) + 2m_(e))c^(2)` and `Q_(2) =(M_(x) - M_(y)+ 2m_(e))c^(2)`

Text Solution

Verified by Experts

For `beta^(-)`, decay, `""_(z)X^(A) to ""_(z+1)Y^(A) + ""_(-1)e^(0) +barv+Q_(1)`
Q = energy for this decay is given by
`Q_(1)=[m(""_(2)X^(A))-m(""_(z+1)Y^(A))]c^(2)`
Where mN represents mass of nucleus and m represent mass of an atom
`therefore Q_(1) =(M_(x) -M_(y))c^(2)`
(ii) For `beta^(-)`, decay: `""_(Z)X^(A) to ""_(z+1)Y^(A) +""_(1)e^(0) +v +Q_(2)`
Q-energy for this decay is given by:
`Q_(2)=[m(""_(Z)X^(A))-m(""_(z-1)Y^(A))-2m_(e)]c^(2)`
`therefore Q_(2) =(M_(x)-M_(y) -2m_(e))c^(2)`
The correct option is (a).
Promotional Banner

Topper's Solved these Questions

  • NUCLEI

    MODERN PUBLICATION|Exercise CHAPTER PRACTICE TEST FOR BOARD EXAMINATION|15 Videos
  • NUCLEI

    MODERN PUBLICATION|Exercise COMPETITION FILE (INTEGER TYPE QUESTIONS)|10 Videos
  • MOVING CHARGES AND MAGNETISM

    MODERN PUBLICATION|Exercise CHAPTER PRACTICE TEST|13 Videos
  • RAY OPTICS AND OPTICAL INSTRUMENTS

    MODERN PUBLICATION|Exercise CHAPTER PRACTICE TEST|14 Videos

Similar Questions

Explore conceptually related problems

M_(x) and M_(y) denote the atomic masses of the parent and the dougther nuclei respectively in a radioactive decay. The Q - value for a beta- decay is Q_(1) and that for a beta^(+) decay is Q_(2) . If m_(e) denotes the mass of an electrons, then which of the following statements is correct?

If 'P' denotes +, 'Q' denotes -, 'R' denotes ×, and 'S' denotes ÷, which of the following statements is correct?

The nuclide X undergoes alpha -decay and another nuclides Y undergoes beta^(ɵ) -decay, which of the following statement "is"//"are" correct?

In beta -decay, the Q-value of the process is E. Then

In a radioactive decay, neither the atomic number nor the mass number changes. Which of the following particles is emitted in the decay?

A nuclear of mass M +deltam is at rest and decay into two daughter nuclei of equal mass (M)/(2) each speed is c The binding energy per nucleon for the nucleus is E_(1) and that for the daugther nuclei is E_(2) Then

A radioactive element decays by beta- emission. If mass of parent and daughter nucliede are m_(1) and m_(2) respectively, caluclate energy liberated during the emission.