JEE Main 2022 (Online) 27th June Morning Shift | Atoms and Nuclei Question 102 | Physics

A beam of monochromatic light is used to excite the electron in Li^{+ +} from the first orbit to the third orbit. The wavelength of monochromatic light is found to be x $$\times$$ 10^$$-$$10 m. The value of x is ___________.

[Given hc = 1242 eV nm]

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JEE Main 2022 (Online) 24th June Evening Shift

Numerical

-1

Out of Syllabus

A sample contains 10^$$-$$2 kg each of two substances A and B with half lives 4 s and 8 s respectively. The ratio of their atomic weights is 1 : 2. The ratio of the amounts of A and B after 16 s is $${x \over {100}}$$. The value of x is ___________.

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JEE Main 2021 (Online) 27th August Evening Shift

Numerical

-1

X different wavelengths may be observed in the spectrum from a hydrogen sample if the atoms are exited to states with principal quantum number n = 6 ? The value of X is ______________.

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JEE Main 2021 (Online) 27th July Evening Shift

Numerical

-1

The K_$$\alpha$$ X-ray of molybdenum has wavelength 0.071 nm. If the energy of a molybdenum atoms with a K electron knocked out is 27.5 keV, the energy of this atom when an L electron is knocked out will be __________ keV. (Round off to the nearest integer)

[h = 4.14 $$\times$$ 10^$$-$$15 eVs, c = 3 $$\times$$ 10⁸ ms^$$-$$1]

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