Book Store

Download books and chapters from book store.
Currently only available for.
CBSE

NEET Physics : Nuclei

Multiple Choice Questions

101.

A radioactive nucleus is being produced at a constant rate $α$ per second. Its decay constant is λ. If N₀ are the number of nuclei at time t = 0, then the maximum number of nuclei possible are

N₀ + $\frac{α}{λ}$
N₀
$\frac{λ}{α}$ + N₀
$\frac{α}{λ}$

102.

Assertion: Nuclei having mass number about 60 are most stable.

Reason: When two or more light nuclei are combined into a heavier nucleus, then the binding energy per nucleon will increase.

If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false

103.

A nucleus of mass number 220 decays by $α$ decay. The energy released in the reaction is 5 MeV. The kinetic energy of an $α$ -particle is

$\frac{1}{54}$ MeV
$\frac{27}{11}$ MeV
$\frac{54}{11}$ MeV
$\frac{55}{54}$ MeV

104.

N₁ atoms of a radioactive element emit N₂ beta particles per second. The decay constant of the element is ( m s^-1 )

N₁/N₂
N₂/N₁
N₁ ( ln2 )
N₂ ( ln2 )

105.

If the half lives of a radioactive element for $α$ and β decay are 4 years and 12 years respectively, the ratio of its initial activity and that after 12 years will be

6.25 %
12.5 %
25 %
50 %

106.

The intensity of gamma radiation from a given source is I. On passing through 36 mm of lead, it is reduced to l/8. The thickness of lead which will reduce the intensity to l/2 will be

18 mm
12 mm
6 mm
9 mm

107.

Assertion: It is desirable to slow down fast moving neutrons to sustain controlled chain reactions.

Reason: Slow moving neutrons efficiently collides with U²³⁵.

If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If assertion and reason are false.

108.

What is the ratio of Bohr magnetron to the nuclear magnetron?

m_p/m_e
$m_{p}^{2} / m_{e}^{2}$
1
$\frac{m_{e}}{m_{p}}$

109.

Assertion: It is very easy to detect neutrino in nature.

Reason: It has high affinity to interact with matter.

If both assertion and reason are true and reason is the correct explanation of assertion.
If both asertion and reason are true and reason is not correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.

110.

Two radioactive substances A and 8 have decay constants 5A and A respectively. At I =0, they have the same number of nuclei. The ratio of number of nuclei of A to those of 8 will be (1/e² ) after a time

4λ
2λ
$\frac{1}{2 λ}$
$\frac{1}{4 λ}$

Do a good deed today
Refer a friend to Zigya

Book Store

Subject

NEET Physics : Nuclei

Multiple Choice Questions