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Multiple choice nuclear reactions nuclear structure nuclei atomic nuclei physics

Consider a hypothetical annihilation of a stationary electron with a stationary positron. What is the wavelength of resulting radiation?

  1. $\dfrac{h}{m _{0}c}$

  2. $\dfrac{h}{2m _{0}c}$

  3. $\dfrac{2h}{m _{0}c}$

  4. $\dfrac{h}{4\pi m _{0}c}$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
According to De Broglie eave length
$\lambda =\dfrac { h }{ mc } \quad \quad \quad E=\dfrac { hc }{ \lambda  } $
                             $\lambda =\dfrac { hc }{ E } =hc$
When an electron and a positron collide then a hypothetical annihilation of a stationary electron with a stationary position.
Multiple choice nuclear reactions nuclear structure nuclei atomic nuclei physics

The atomic mass of $7 ^ { N ^ { 15 } }$ is 15.000108 a.m.u. and that  is of $8 ^ { \bigcirc ^ { 16 } }$ 15.994915 a.m.u. If the mass of a proton is 1.007825 a.m.u. then the minimum energy provided to remove the least tightly bound proton is

  1. 0.0130181 MeV

  2. 12.13 MeV

  3. 13.018 MeV

  4. 12.13 eV
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

$\begin{array}{l} \left( { { M _{ n } }+{ M _{ H } }-{ M _{ 0 } } } \right) \times 431.5 \ =\left[ { 15.000108+1.007827-15.994915 } \right] \times 431 \ =12.13\, Mev \end{array}$

Multiple choice nuclear reactions nuclear structure nuclei atomic nuclei physics

The energy of the reaction ${ Li }^{ 7 }+p\longrightarrow 2{ He }^{ 4 }$ is (the binding energy per nucleon in ${ Li }^{ 7 }$ and ${ He }^{ 4 }$ nuclei are 5.60 and 7.06 MeV respectively.)

  1. 17.3 MeV`

  2. 1.73 MeV

  3. 1.46 MeV

  4. Depends on binding energy of proton
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The energy released will depend on the energy equivalent of proton, taking its mass to be $1amu$ or
 corresponding energy as $931.5Mev$
we get energy released as $Q=E _{reactant} -E _{product}=7\times 5.6 +931.5 -2\times4\times  7.06=914.22Mev$

Multiple choice nuclear reactions nuclear structure nuclei atomic nuclei physics

The binding energy per nucleon of deuteron $(^2 _1 H)$ and helium nucleus $(^4 _2 He)$ is 1.1 MeV and 7 MeV respectively. If two deuteron nuclei react to form a single helium nucleus, then the energy released is

  1. 23.6 MeV

  2. 26.9 MeV

  3. 13.9 MeV

  4. 19.2 MeV
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Energy released = BE(products) - BE(reactants). BE(He) = 4 * 7 = 28 MeV. BE(2 deuterons) = 2 * (2 * 1.1) = 4.4 MeV. Energy released = 28 - 4.4 = 23.6 MeV.

Multiple choice nuclear reactions nuclear structure nuclei atomic nuclei physics

Find the  binding energy of a H atom in the state n = 2

  1. 2.1 eV

  2. 3.4 eV

  3. 4.2 eV

  4. 2.8 eV
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The energy levels of a hydrogen atom are given by E_n = -13.6 / n^2 eV. For n = 2, E_2 = -13.6 / 4 = -3.4 eV. The binding energy is the magnitude of this energy, which is 3.4 eV.

Multiple choice nuclear reactions nuclear structure nuclei atomic nuclei physics

The binding energy per nucleon of deutron $(^2 _1 H)$ and helium nucleus $(^4 _2 He)$ is 1.1 MeV and 7 MeV respectively. If two deutron nuclei react to form a single helium nucleus, then the energy released is

  1. $23.6 MeV$

  2. $26.9 MeV$

  3. $13.9 MeV$

  4. $19.2 MeV$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Energy released = BE(He) - 2 * BE(deuteron) = (4 * 7) - 2 * (2 * 1.1) = 28 - 4.4 = 23.6 MeV.

Multiple choice nuclear reactions nuclear structure nuclei atomic nuclei physics

Binding energy per nucleon is $8.5 \text { MeV for } A = 120$ and is $7.6 \mathrm { MeV } \text { for } \mathrm { A } = 240$ Suppose a nucleus with $A = 240$ breaks into two nuclei of nearly equal mass numbers then which of the following is correct

  1. 216 MeV energy is released.

  2. 21 MeV energy is to be given from outside

  3. 220 MeV energy is released.

  4. no energy is released.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Initial BE = 240 * 7.6 = 1824 MeV. Final BE = 2 * (120 * 8.5) = 2 * 1020 = 2040 MeV. Energy released = 2040 - 1824 = 216 MeV.

Multiple choice nuclear reactions nuclear structure nuclei atomic nuclei physics

Energy released if mass of $2\ amu$ is converted into energy is :

  1. $1.5 \times 10^{-10}\ J$

  2. $3 \times 10^{-10}\ J$

  3. $1863\ J$

  4. $931.5 \Mev$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

$ E = \Delta m c^{2}$
    $ = (2 \times 1.67 \times 10^{-27}  kg) \times (3 \times 10^{8} \frac{m}{s})^{2} $
    $ = 3 \times 10^{-10}  J$

Multiple choice nuclear reactions nuclear structure nuclei atomic nuclei physics

When an electron and a positron are annihilated, then the number of photons produced is

  1. 2

  2. 1

  3. 3

  4. 4
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Two photons are produced during the annihilation of an electron and a positron along with $1.02$ MeV released energy.

Multiple choice nuclear reactions nuclear structure nuclei atomic nuclei physics

Consider the nuclear reaction: $\mathrm { X } ^ { 200 } \longrightarrow \mathrm { A } ^ { 110 } + \mathrm { B } ^ { 20 }$If the binding energy per nucleon for $\mathrm { X } , \mathrm { A }$ and $\mathrm { B }$ is $7.4 \mathrm { MeV } , 8.2 \mathrm { MeV }$ and 8.2$\mathrm { MeV }$ respectively, what is the energy relesed?

  1. $200$ $\mathrm { MeV }$

  2. $160$ $\mathrm { MeV }$

  3. $110$ $\mathrm { MeV }$

  4. $90$  $\mathrm { MeV }$
Reveal answer Fill a bubble to check yourself
B Correct answer