Are these Nuclei notes free?

Yes. The full 7-page Nuclei sheet is free inside CapCompass, which runs in your browser with no account needed.

What does the Nuclei revision sheet cover?

Protons, Neutrons, Nucleons, Reading a nucleus, Isotopes, isobars, isotones, Size and density of the nucleus, Size formulas, radius, volume, mass, density, Limits of nuclear size.

Is this for Class 12 CBSE Physics?

It is written from the NCERT syllabus, so it serves CBSE and any board that follows NCERT for Physics.

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Nuclei — Class 12 CBSE Physics revision notes

A 7-page visual revision sheet for Nuclei, written for Class 12 CBSE Physics. Formulas, diagrams and the traps that cost marks, laid out to be read the night before rather than the term before. Free, and it opens inside CapCompass.

Nuclei revision notes, page 1 of 7 — A preview of page 1 — all 7 pages open full size in the app.

Nuclei in one look

mass turns into binding energy, and binding energy is why splitting or joining nuclei releases power

Protons: atomic number, fixes which element it is
Neutrons: no charge, adds mass without adding charge
Nucleons: mass number, total count of protons and neutrons

Reading a nucleus

symbol ^A_ZX: X the element, Z protons, A nucleons
neutrons: N=A-Z
nuclear sizes in fm: 1 fm = 10^-15 m
atomic mass unit u: one twelfth of a carbon-12 atom
1 u is equivalent to 931.5 MeV
nucleons are held by the strong nuclear force, not gravity or Coulomb

Isotopes, isobars, isotones

family	same	different	example
isotopes	Z	N and A	hydrogen, deuterium, tritium
isobars	A	Z and N	carbon-14 and nitrogen-14
isotones	N	Z and A	carbon-13 and nitrogen-14

Page 1 of 7. The full sheet, all 7 pages, opens free in the app.

What this Nuclei sheet covers

Protons
Neutrons
Nucleons
Reading a nucleus
Isotopes, isobars, isotones
Size and density of the nucleus
Size formulas
radius
volume
mass
density
Limits of nuclear size
Mass defect and binding energy
mass defect
binding energy
with Δm in u
binding energy per nucleon
Limits of binding
Binding energy per nucleon vs mass number
The nuclear force
Fission vs fusion
Fission
Fusion
The chain reaction
The three kinds of decay
The decay law
activity, rate of decay
number remaining
half-life
mean life
Limits of the decay law
Mean life, activity and decay chains
Q value of a reaction
Symbols
Traps that cost marks
Tricks that save time

Open the full Nuclei sheet →Free, works offline, no account needed. All 7 pages, plus a study plan built around your own exam dates.

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