Consider the following ....|NUCLEAR PHYSICS|JEE-Main 2021

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JEE MAIN 2021

27-07-2021 S2

Question

Consider the following statements :
A. Atoms of each element emit characteristics spectrum.
B. According to Bohr’s Postulate, an electron in a hydrogen atom, revolves in a certain stationary orbit.
C. The density of nuclear matter depends on the size of the nucleus.
D. A free neutron is stable but a free proton decay is possible.
E. Radioactivity is an indication of the instability of nuclei.
Choose the correct answer from the options given below :

Select the correct option:

A

A, B C, D and E

B

A, B and E only

C

B and D only

D

A, C and E only

✓ Correct! Well done.

✗ Incorrect. Try again or view the solution.

Solution

(A) True, atom of each element emits characteristic spectrum.
(B) True, according to Bohr’s postulates
and hence electron resides into orbits of specific radius called stationary orbits.
(C) False, density of nucleus is constant
(D) False, A free neutron is unstable decays into proton and electron and antineutrino.
(E) True unstable nucleus show radioactivity

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