1
JEE Main 2022 (Online) 26th July Evening Shift
Numerical
+4
-1

Consider an imaginary ion $${ }_{22}^{48} \mathrm{X}^{3-}$$. The nucleus contains '$$a$$'% more neutrons than the number of electrons in the ion. The value of 'a' is _______________. [nearest integer]

2
JEE Main 2022 (Online) 26th July Morning Shift
Numerical
+4
-1

The wavelength of an electron and a neutron will become equal when the velocity of the electron is $$x$$ times the velocity of neutron. The value of $$x$$ is ____________. (Nearest Integer)

(Mass of electron is $$9.1 \times 10^{-31} \mathrm{~kg}$$ and mass of neutron is $$1.6 \times 10^{-27} \mathrm{~kg}$$ )

3
JEE Main 2022 (Online) 25th July Evening Shift
Numerical
+4
-1

When the excited electron of a H atom from n = 5 drops to the ground state, the maximum number of emission lines observed are _____________.

4
JEE Main 2022 (Online) 28th June Morning Shift
Numerical
+4
-1

If the work function of a metal is 6.63 $$\times$$ 10$$-$$19J, the maximum wavelength of the photon required to remove a photoelectron from the metal is ____________ nm. (Nearest integer)

[Given : h = 6.63 $$\times$$ 10$$-$$34 J s, and c = 3 $$\times$$ 108 m s$$-$$1]