1
JEE Main 2023 (Online) 1st February Evening Shift
MCQ (Single Correct Answer)
+4
-1
Change Language

An electron of a hydrogen like atom, having $$Z=4$$, jumps from $$4^{\text {th }}$$ energy state to $$2^{\text {nd }}$$ energy state. The energy released in this process, will be :

(Given Rch = $$13.6~\mathrm{eV}$$)

Where R = Rydberg constant

c = Speed of light in vacuum

h = Planck's constant

A
$$10.5 ~\mathrm{eV}$$
B
$$40.8 ~\mathrm{eV}$$
C
$$13.6 ~\mathrm{eV}$$
D
$$3.4 ~\mathrm{eV}$$
2
JEE Main 2023 (Online) 1st February Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language

The mass of proton, neutron and helium nucleus are respectively $$1.0073~u,1.0087~u$$ and $$4.0015~u$$. The binding energy of helium nucleus is :

A
$$28.4~\mathrm{MeV}$$
B
$$56.8~\mathrm{MeV}$$
C
$$7.1~\mathrm{MeV}$$
D
$$14.2~\mathrm{MeV}$$
3
JEE Main 2023 (Online) 31st January Evening Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
The radius of electron's second stationary orbit in Bohr's atom is R. The radius of 3rd orbit will be
A
2.25R
B
$3 \mathrm{R}$
C
$\frac{\mathrm{R}}{3}$
D
$9 \mathrm{R}$
4
JEE Main 2023 (Online) 31st January Morning Shift
MCQ (Single Correct Answer)
+4
-1
Out of Syllabus
Change Language

A free neutron decays into a proton but a free proton does not decay into neutron. This is because

A
neutron is an uncharged particle
B
neutron has larger rest mass than proton
C
neutron is a composite particle made of a proton and an electron
D
proton is a charged particle
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