Tag: nuclear structure

Quizzes (0) Questions (103)

Questions Related to nuclear structure

Multiple choice nuclear reactions nuclear structure nuclei atomic nuclei physics

In each fission energy of $200\ MeV$ is released. How many acts of fission must occur per second to produce a power of $1\ kw$?

  1. $3.1\times 10^{13}$
  2. $1.3\times 10^{16}$
  3. $1.4\times 10^{16}$
  4. $2.3\times 10^{15}$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Power required is P = 1 kW = 1000 J/s. Energy released per fission is 200 MeV = 200 * 10^6 * 1.6 * 10^-19 J = 3.2 * 10^-11 J. The number of fissions per second n is given by P = n * E, so n = 1000 / (3.2 * 10^-11) = 3.125 * 10^13 fissions per second, which matches option A.

Multiple choice nuclear reactions nuclear structure nuclei atomic nuclei physics

The binding energy of  $ _ { 17 } \mathrm { CI } ^ { 35 }$  nucleus is  $298\ \mathrm { MeV }.$  Find its atomic mass. The mass of hydrogen atom  $({ _{ 1 }{ H } }^{ 1 })$  is  $1.008143\  \mathrm { amu }$  and that of a neutron is  $1.008986\  \mathrm { amu }.$  Given  $1\  \mathrm { amu } = 931\  \mathrm { MeV }.$

  1. $148$
  2. $298$
  3. $340$
  4. $348$
Reveal answer Fill a bubble to check yourself
D Correct answer
Multiple choice nuclear reactions nuclear structure nuclei atomic nuclei physics

In a working nuclear react, cadmium rods (control rods) are used to:-

  1. Speed up neutrons

  2. Slow down neutrons

  3. Absorb some neutrons

  4. Absorb all neutrons
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Cadmium rods are used in nuclear reactors to absorb neutrons, which helps control the rate of the fission chain reaction.

Multiple choice nuclear reactions nuclear structure nuclei atomic nuclei physics

In the nuclear reaction ; $ _{92}U^{238}\rightarrow _{z}Th^{A}+ _{2}He^{4}$ the values of A and Z are: 

  1. A=230,Z=8

  2. A=234,Z=90

  3. A=228, Z=94

  4. A=232, Z=
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In alpha decay, the mass number decreases by 4 and the atomic number decreases by 2. For U-238, A becomes 238 - 4 = 234 and Z becomes 92 - 2 = 90.

Multiple choice nuclear reactions nuclear structure nuclei atomic nuclei physics

Out side a nucleus 

  1. Neutron is stable

  2. Proton and neuron both are stable

  3. Neutrons is unstable

  4. Neither neutrons nor proton is stable
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Free neutrons outside a nucleus are unstable and decay with a half-life of about 10.2 minutes. Protons, however, are stable particles. The statement 'Neutrons is unstable' (despite the grammatical error) correctly identifies that free neutrons undergo beta decay.

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.