### IIT JAM PHYSICS

NEWTON LAWS OF MOTION
Tension
FRICTION
Friction
VELOCITY AND ACCELERATION
CENTRAL FORCES
Gravitation
UNIFORMLY ROTATING FRAME- CENTRIFUGAL AND CORIOLIS FORCES
CONSERVATION LAWS
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CENTRE OF MASS AND VRIABLE MASS SYSTEMS
RIGID BODY DYNAMICS
FLUID DYNAMICS
COULOMB LAW AND ELECTRIC FIELD
GAUSS LAW OF ELECTROSTATICS AND APPLICATIONS
Capacitance
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WORK AND ENERGY IN ELECTROSTATICS
Capacitors
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CURRENT ELECTRICITY
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DC CIRCUITS
RC Circuit
LR circuit
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AC CIRCUITS
AC Circuit
MAXWELL EQUATIONS and poynting vector
ELECTROMAGNETIC WAVES
REFLECTION AND REFRACTION OF EM WAVES AT THE INTERFACE OF TWO DIELECTRICS
Section 3: MATHEMATICAL PHYSICS
MULTIPLE INTEGRAL
VECTOR CALCULUS
DIFFERENTIAL EQUATIONS
MATRICES
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Jacobian
FOURIER SERIES
PARTICLE NATURE OF WAVE
WAVE NATURE OF PARTICLE
H ATOM
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SCHRONDINGER WAVE EQUATION
NUCLEAR PHYSICS
SPECIAL THEORY OF RELATIVITY
SIMPLE HARMONIC OSCILLATION
DAMPED AND FORCED OSCILLATION
WAVES
Waves
GEOMETRICAL OPTICS
Thin Lens
INTERFERENCE
Thin Films
DIFFRACTION
Single Slit
Double Slit
POLARIZATION OF LIGHT
THERMAL EXPANSION
CALORIMETRY
Calorimetry
TRANSMISSION OF HEAT
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# Gamma Decay

When the nucleus in the excited state passes to the ground state or to the lower excited state from higher excited state, it emits a high energy photon. This photon emitted from a nucleus in an excited state is known as $\gamma$ rays.

$\ {z} X^A \rightarrow \ {z}X^{A} + \gamma$

The $\gamma$ emission must satisfy following conservation laws

(a) Conservation of charge
(b) Conservation of mass energy : If transition takes place from an excited state $E_2$ to lower energy state $E_1$ then

$E_2 - E_1 = h \mu$

where v is frequency of $\gamma$ ray photon

(c) Conservation of linear and angular momentum : Emission of $\gamma$-ray must make the daughter nucleus recoil with the same momentum in opposite direction. If parent nucleus is at rest. If M is mass and V is velocity of daughter nucleus

$\dfrac{h \nu}{c} + MV = 0$

Angular momentum must also be conserved.

Intrinsic angular momentum or spin of photon = $\dfrac{h}{2 \pi} = \hbar$

Internal Conversion

It is the one step process of transition of nucleus from higher excited state to ground state by direct transfer of energy through the electromagnetic interaction from a nucleus in excited state to one of its orbital electrons so that it is ejected from atom with kinetic energy E given by

$E = E_e - W$

Where E is available excitation energy (ie. energy given out by excited nucleus). W is binding energy of the ejected electron in its shell of origin. The emitted electron is called conversion electron. Here $\gamma$ ray is not produced and it is one step process.
The internal conversion does not complete with $\gamma$ rays emission in the sense that one process inhibits the other. The processes are independent alternatives.