JEE Main 2019 (Online) 8th April Morning Slot | Atoms and Nuclei Question 184 | Physics

Radiation coming from transitions n = 2 to n = 1 of hydrogen atoms fall on He⁺ ions in n = 1 and n = 2 states. The possible transition of helium ions as they absorb energy from the radiation is :

n = 1 $$ \to $$ n = 4

n = 2 $$ \to $$ n = 5

n = 2 $$ \to $$ n = 4

n = 2 $$ \to $$ n = 3

JEE Main 2019 (Online) 12th January Evening Slot

MCQ (Single Correct Answer)

-1

Out of Syllabus

In a radioactive decay chain, the initial nucleus is $${}_{90}^{232}$$Th. At the end there are 6 $$\alpha $$-particles and 4 $$\beta $$-particles which are emitted. If the end nucleus is $${}_Z^A$$X, A and Z are given by :

A = 208; Z = 80

A = 208; Z = 82

A = 200; Z = 81

A = 202; Z = 80

JEE Main 2019 (Online) 12th January Morning Slot

MCQ (Single Correct Answer)

-1

A particle of mass m moves in a circular orbit in a central potential field U(r) = $${1 \over 2}$$ kr². If Bohr 's quantization conditions are applied, radii of possible orbitls and energy levels vary with quantum number n as :

r_n $$ \propto $$ $$\sqrt n $$, E_n $$ \propto $$ n

r_n $$ \propto $$ $$\sqrt n $$, E_n $$ \propto $$ $${1 \over n}$$

r_n $$ \propto $$ n, E_n $$ \propto $$ n

r_n $$ \propto $$ n², E_n $$ \propto $$ $${1 \over {{n^2}}}$$

JEE Main 2019 (Online) 11th January Evening Slot

MCQ (Single Correct Answer)

-1

In a hydrogen like atom, when an electron jumps from the M-shell to the L-shell, the wavelength of emitted radiation is $$\lambda $$. If an electron jumps from N-shell to the L-shell, the wavelength of emitted radiation will be:

$${{25} \over {16}}$$ $$\lambda $$

$${{27} \over {20}}$$ $$\lambda $$

$${{16} \over {25}}$$ $$\lambda $$

$${{20} \over {27}}$$ $$\lambda $$

PREVIOUS NEXT

Questions Asked from Atoms and Nuclei (MCQ (Single Correct Answer))

Number in Brackets after Paper Indicates No. of Questions