 ## NATA 2020 Physics Syllabus

(Updated)

Electric charges and Fields

Electric Charge.
The physical properties of matter which allows it to experience a special kind of force when kept
under the influence of the electromagnetic field is called Electric Charge.
Formula: Q = I.t
Q is the electric charge
I is the electric current
t is the time.

Columb’s Law
The magnitude of the electrostatic force of attraction or repulsion between Two point charges is
directly proportional to the product of the magnitudes of charges and inversely proportional to
the square of the distance between them.
The Coulomb’s Law is given by the expression:
Fe = kq1q2/r2

Electric field
Electric field is defined as the electric force per unit charge. The direction of the field is taken to
be the direction of the force it would exert on a positive test charge. The electric field is radially
outward from a positive charge and radially in toward a negative point charge.
𝐸 = 𝒇𝒒

Topic-2

Electric potential

Electric potential
Electric potential of a point in an electric field is the amount of work done in bringing a unit charge
(without acceleration) from infinity to that point.

Electric potential (v) = 𝑸/𝒓

Capacitance
Electric potential 'V' is directly proportional to charge ’Q' means when Q will increase the
electric potential of the capacitor also increases. So, because they both are proportional to each other the ratio of Q and V is a constant:

C=    𝑄 (𝐶ℎ𝑎𝑟𝑔𝑒)
𝑉 (𝑃𝑜𝑡𝑒𝑛𝑡𝑖𝑎𝑙)

Topic-3

Current Electricity

Current Electricity
An electric charge will experience a force if an electric field is applied. If it is free to move, it will
thus move contributing to a current. In nature, free charged particles do exist like in upper strata
of atmosphere called the ionosphere

Ohm’s Law:
V α R
V = RI

Topic-4

Magnetic Effects of Current
The term "magnetic effects of current " means that " a current flowing in a wire produces
a magnetic field round it ". the magnetic effect of current was discovered by Oersted found that
a wire carrying a current was able to deflect a magnetic needle.

Magnetic field due to current carrying conductor
When an electric current through a metallic conductor produces a magnetic field around it. In order to find the direction of the field produced let us repeat the activity in the following way –

Topic - 5

Moving Charges and magnetism

Moving Charges and magnetism
A charged particle moving without acceleration produces an electric as well as a magnetic field.
It produces an electric field because it's a charge particle. But when it is at rest, it doesn't produce
a magnetic field. All of a sudden when it starts moving, it starts producing a magnetic field. Why?
What happens to it when it starts moving? What makes it produce a magnetic field when it starts
moving?
Lorentz Force
𝐹 = 𝑞[𝐸(𝑟) + 𝑉 × 𝐵 (𝑟)] = 𝐹𝐸𝑙𝑒𝑐𝑡𝑟𝑖𝑐+𝐹𝑀𝑎𝑔𝑛𝑒𝑡𝑖𝑐

Topic - 6

Magnetism and Matter

Magnetism and Matter
Magnetism is a phenomenon by the virtue of which there develops an attracting or repulsive
force between two magnetic objects.

Cause of Magnetism
Motion of electrons in an orbit within the nucleus.
Spin of electrons around its axis.

In modern physics, matter is defined as a substance which is made of various types of particles
of various size and matter each. In simple language, substance which has mass and occupies
space is known as Matter.
For Example: Hematite (main ore of iron), oxides such as nickel oxide.

Three different states of matter:
Solid
Liquid
Gas

Topic - 7

Electromagnetic Induction

Electromagnetic Induction
The discovery and understanding of electromagnetic induction are based on a long series of
experiments carried out by Faraday and Henry

That a voltage is induced in a circuit whenever relative motion exists between a conductor and
a magnetic field and that the magnitude of this voltage is proportional to the rate of change of
the flux”.
= 𝜷. 𝒍. 𝝊 𝒗𝒐𝒍𝒕𝒔
If the conductor does not move at right angles (90°) to the magnetic field then the angle θ° will
be added to the above expression giving a reduced output as the angle increases:
= 𝜷. 𝒍. 𝝊 𝐬𝐢𝐧 𝜽 𝒗𝒐𝒍𝒕𝒔

Topic - 8

Alternating Current

Alternating Current
Either as a voltage switching polarity or as a current switching direction back and forth, this
“kind” of electricity is known as Alternating Current (AC).

Whereas the familiar battery symbol is used as a generic symbol for any DC voltage source, the
circle with the wavy line inside is the generic symbol for any AC voltage source.
One might wonder why anyone would bother with such a thing as AC. It is true that in some
cases AC holds no practical advantage over DC.

Topic - 9
Ray optics and optical instruments

Ray optics and optical instruments
(I) Ray of Light A straight line drawn in the direction of propagation of light is called a ray of light.

(ii) Luminous Objects The objects which emits its own light, are called luminous objects, e.g., sun,
other stars, an oil lamp etc.
(iii) Non-Luminous Objects The objects which do not emit its own light but become visible due
to the reflection of light falling on them, are called non-luminous objects, e.g., moon, table, chair.
trees etc.

Optical Instruments
Power of a concave lens (P)

P = (100/x) diopter, here ‘x’ is the distance of far point of the defective eye, in ‘cm’.

Magnifying power or magnification of a simple microscope

M = 1+ (D/f), here ‘D’ is the distance of distinct vision and ‘f’ is the focal length.

Magnifying power or magnification of a compound microscope: -

M = L/f0[1+(D/fe)] where f0 is the focal length of object, fe is the focal lengthy of eyepiece
and L is the length of microscope tube.

Magnifying power or magnification of astronomical telescope (Normal Adjustment)
M = f0/fe

Magnifying power or magnification of astronomical telescope (When the final image is formed at the distance of distinct vision)

M = (f0/fe) [(fe+D)/D]

Magnifying power or magnification of Galileo’s telescope: -

M = F/f

Topic - 10

Wave optics
Wave Optics
Wave Optics, is the branch of optics that studies interference, diffraction, polarization, and
other phenomena for which the ray approximation of geometric optics is not valid. This usage
tends not to include effects such as quantum noise in optical communication, which is studied
in the sub-branch of coherence theory

Maxwell Electromagnetic Theory
According to Maxwell, light is not a mechanical wave. It is an electromagnetic
wave which is transverse in nature which travels with a finite speed given by;

C =   𝟏
𝝁𝟎𝜺𝟎                = 3 x 108 m/s

Topic - 11
Dual Nature of Matter and Radiation

Dual Nature of Matter and Radiation

We will study the dual nature of matter which will be explained by Wave-particle duality
postulates. According to this postulate, all particles exhibit both wave properties and particle properties.

Electron emission

We know that metals have free electrons (negatively charged particles) that are responsible for their conductivity. However, the free electrons cannot normally escape out of the metal
surface. If an electron attempts to come out of the metal, the metal surface acquires a positive charge and pulls the electron back to the metal One electron volt is the energy gained by an electron when it has been accelerated by a
potential difference of 1 volt, so that 1 eV = 1.602 ×10 –19 J.

Particle nature of light: the photon

Photoelectric effect thus gave evidence to the strange fact that light in interaction with matter
behaved as if it was made of quanta or packets of energy, each of energy h ν.
Each photon has energy E (=hν) and momentum p (= h ν/c), and speed c, the speed of light.

Topic - 12

Atoms
An atom is the smallest particle into which an element can be divided without losing its chemical
identity. Atoms consist of a heavy central nucleus surrounded by a cloud of negatively charged
particles called electrons. The nucleus contains positive particles (protons) and electrically
neutral particles (neutrons). The number of protons is called the atomic number.
If an atom or molecule becomes electrically charged by gaining or losing one or more electrons,
it becomes an ion. If the atom gains electrons, it has a negative charge. If it loses electrons, it has a positive charge.

Topic - 13

Nuclei
Nuclei is the plural of nucleus which is a group of protons and neutrons at the middle of every atom. Nuclear physics investigates things like the makeup of a Nucleus, the forces that interact within the nucleus and what makes up not only the nucleus but also what makes up those particles

Nuclei are bound together by the residual strong force (nuclear force). The residual strong force is a minor residuum of the strong interaction which binds quarks together to form protons and neutrons.

Topic - 14
Semiconductor Electronics
A semiconductor device is an electronic component that relies on the electronic properties of a semiconductor material (primarily silicon, germanium, and gallium arsenide, as well as organic semiconductors) for its function. Semiconductor devices have replaced vacuum tubes in most applications. They use electrical conduction in the solid state rather than the gaseous state or thermionic emission in a vacuum.

Doping a semiconductor with a small proportion of an atomic impurity, such
as phosphorus or boron, greatly increases the number of free electrons or holes within the
semiconductor. When a doped semiconductor contains excess holes, it is called a p-type semiconductor (p for positive electric charge); when it contains excess free electrons, it is called an n-type semiconductor (n for negative electric charge). A majority of mobile charge carriers have negative charge. The manufacture of semiconductors controls precisely the location and concentration of p- and n-type dopants. The connection of n-type and p-type semiconductors form p–n junctions.

Topic - 15

Materials
Materials themselves include ceramics, polymers, composites, bio-materials, and
electronic materials. A career in materials physics would involve synthesizing the different
physical sciences: chemistry, continuum physics, and condensed matter physics.

Topic - 16

Devices and Simple circuits

Feedback amplifier and transistor oscillator
In an amplifier, we have seen that a sinusoidal input is given which appears as an amplified
signal in the output. This means that an external input is necessary to sustain ac signal in the
output for an amplifier. In an oscillator, we get ac output without any external input signal. In
other words, the output in an oscillator is self-sustained
𝝂 =𝟏
𝟐𝝅𝑳𝑪

Integrated circuits
The concept of fabricating an entire circuit (consisting of many passive components like R and C and active devices like diode and transistor) on a small single block (or chip) of a semiconductor has revolutionized the electronics technology. Such a circuit is known as Integrated Circuit (IC).

## NATA Drawing Question 2020

"Future Design Career provides you with all the information related to Design Career. This website is intended to guide All students so that they can choose the right career and make their future better & bright career."