WB JEE 2008 | Atoms and Nuclei Question 1 | Physics

The ionisation potential of hydrogen atom is $$-$$13.6 eV. An electron in the ground state of a hydrogen atom absorbs a photon of energy 12.75 eV. How many different spectral lines can one expect when the electron make a downward transition?

WB JEE 2008

MCQ (Single Correct Answer)

-0.25

Which of the following statements is correct?

The rest mass of a stable nucleus is less than the sum of the rest masses of its separated nucleons.

The rest mass of a stable nucleus is greater than the sum of the rest masses of its separated nucleons.

In nuclear fission, energy is released by fusion is two nuclei of medium mass (approximately 100 amu)

In nuclear fission, energy is released by fragmentation of a very low nucleus.

WB JEE 2025

MCQ (Single Correct Answer)

-0.25

A radioactive nucleus decays as follows :

$$ X \xrightarrow{\alpha} X_1 \xrightarrow{\beta} X_2 \xrightarrow{\alpha} X_3 \xrightarrow{\gamma} X_4 $$

If the mass number and atomic number of ' $X_4$ ' are 172 and 69 respectively, then the atomic number and mass number of ' $X$ ' are

72,180

69,170

68,172

70,172

WB JEE 2025

MCQ (Single Correct Answer)

-0.25

The minimum wavelength of Lyman series lines is $P$, then the maximum wavelength of these lines is

$\frac{4 P}{3}$

$2 P$

$\frac{2 P}{3}$

$\infty$

Questions Asked from MCQ (Single Correct Answer)

WB JEE 2025 (3) WB JEE 2024 (1) WB JEE 2023 (1) WB JEE 2022 (2) WB JEE 2021 (2) WB JEE 2020 (3) WB JEE 2019 (3) WB JEE 2018 (3) WB JEE 2017 (2) WB JEE 2016 (1)

WB JEE Subjects