CIRCULAR MOTION FORMULAE

 

COMPARISON OF ELECTRIC FIELD AND MAGNETIC FIELD

 

ELECTRIC FIELD	MAGNETIC FIELD
Source is “ Charge”	Source is current
Obeys inverse square law	Obeys inverse square law
Obeys principle of superposition	Obeys principle of superposition
It is independent of angle	It is dependent on angle
Electric field lines don’t form close loops	Magnetic field lines form closed loops
Electric field changes kinetic energy of particle	Magnetic field doesn’t change kinetic energy of particle.
A particle experiences electric field whether it is at rest or in motion	A particle experiences magnetic field only in motion and a charge at rest doesn’t experience the magnetic field.

USES OF ISOTOPES

 

Purpose	Isotope Name
IN MEDICINE
For testing blood	Chromium-51
For testing blood circulation	Na-24
For testing brain tumor	Hg-203
Thyroid problem	I-131
Treatment of Cancer	Co-60
For blood disorders	Au-189
For skin diseases	P-31
IN ARCHAEOLOGY
Carbon Dating	C-14
Determining age of meteorites	K-40
Determining age of earth	Pb isotopes
IN AGRICULTURE
For protecting potato crop from earth worm	Co-60
For artificial rains	AgI
For fertilizers	P-32

Types of Nuclei - Isotopes, Isobars, Isotones, Mirror Nuclei, Isoelectronic Species, Isodiaphers

Characteristics of different types of  Nuclei is as follows:

Isotopes

• Same Atomic Number(Z)
• Same number of electrons
• Same number of Protons
• Different Mass Numbers
• Different number of Neutrons
• Same chemical properties
• Different Physical Properties
• Belong to same element

eg: ₁H¹  ,  ₁H² , ₁H³

Isobars

• Different Atomic Number(Z)
• Different number of electrons
• Different number of Protons
• Same Mass Number
• Different number of Neutrons
• Different chemical properties
• Different Physical Properties
• Belong to different elements

eg: ₆C¹⁴  ,  ₇N¹⁴,  ₈O¹⁴

Isotones

• Different Atomic Number(Z)
• Different number of electrons
• Different number of Protons
• Different Mass Number
• Same number of Neutrons
• Different Chemical Properties
• Different Physical Properties
• Belong to different elements

eg: ₁₆S³⁶  ,  ₁₇Cl³⁷

Mirror Nuclei

• Different Atomic Number(Z)
• Different number of electrons
• Different number of Protons
• Same Mass Number
• Different number of Neutrons
• Neutrons and Protons are interchanged 

Isoelectronic Species

Species having equal number of electrons.

Isodiaphers

Nuclides having the same difference between Protons & Neutrons

• Different Atomic Number(Z)
• Different number of electrons
• Different number of Protons(P)
• Different Mass Number(A)
• Different number of Neutrons(N)
• Same (P-N)

eg: ₉₂U²³⁸  ₉₀Th²³⁴

Comparison between "Series" & "Parallel" Combination of Inductors

 Let L1 & L2 are inductance of two Inductors. Ls is series inductance and Lp is parallel inductance for the two Inductors. M is "Mutual inductance".

SERIES COMBINATION	PARALLEL COMBINATION
Ls = L1 +L2   If both coils are placed close to each other, Ls = L1 +L2 ± 2M	Lp = L1L2/L1 +L2   If both coils are placed close to each other, Ls = L1L2 – M2
If ‘n’ coils of equal inductance ‘L’ are put in series, then Ls = nL	If ‘n’ coils of equal inductance ‘L’ are put in series, then Lp = L/n
Ls/Lp = n2	Lp/Ls =1/ n2
Voltage ‘V’ is divided	Voltage ‘V’ is not divided