# PRINCIPLES OF PHYSICS

## Learning outcomes of the course unit

The course aims to provide the student with fundamental knowledge of the laws of

physics and of the application of the laws to the study of the most common

phenomena in order to be able to describe and interpret investigation and

measurement techniques, which will then be used in research or working

laboratories. Particular attention will be placed on measurement units, on estimation of orders of magnitude, appropriate use of

terms and development of ability to synthesize. The fundamental equations will be

explained and applied, with acknowledgement of the limits of their validity, to the

case of simple problems.

The purpose is to transfer knowledge and develop ability, to facilitate understanding at a level which, using advanced and differentiated texts, allows to approach the main themes of General Physics and then provide the basic skills to solve problems of various kinds requiring a physical approach, to interpret results and communicate in an understandable and correct way, developing independent learning skills necessary for subsequent searches.

## Prerequisites

Attendance to the basic Mathematics course is recommended

## Course contents summary

The course is divided essentially into four parts: the first devoted to the traditional Mechanics, the second to Thermodynamics, the third to Electro-Magnetism, the fourth to Optics. Finally some introductory concepts of Modern Physics are given.

1 - The physical quantities, their measurement units and errors inherent to a measurement are introduced. It is then developed the part concerning the motion of bodies, the causes of motion (also rotational) with the relevant laws. Particular attention is paid to the concept of work/energy, to the energy conservation and to the systems in which you can introduce the potential energy.

Examples of non-inertial reference systems with apparent forces are given. The harmonic oscillator (and the harmonic motion) as a model applicable to different physical situations is treated. The principles of conservation of momentum and angular momentum are discussed. The essential concepts of statics and dynamics of fluids, up to Bernoulli's equation are then given.

2 - The essential concepts of thermodynamics, including phase transitions, are given and the behavior of simple thermodynamic systems is illustrated, in accordance with the laws of thermodynamics, up to the heat engines and the various definitions of efficiency. The kinetic theory of gases and its implications are finally discussed.

3 - Electromagnetism is addressed with the aim of presenting in an intuitive and descriptive way the Maxwell's equations and their implications, up to the electromagnetic induction. Moving charges, currents and magnetic fields are discussed with simple examples. Particular attention is paid to the concept of electric potential and electromotive force. DC and AC circuits are analyzed simply by introducing the impedance. The origin of electromagnetic waves is explained and then the nature of light and its polarization properties.

4 - The properties of the light are finally addressed both from a geometrical point of view (reflection, refraction) that electromagnetic (diffraction and interference), describing optical instruments such as mirrors, lenses, lens systems, microscopes, fibers, diffraction gratings.

## Course contents

Mechanics of point masses:

Measurements - Units - Physical quantities - Vectors Operations on vectors - Motion

- Scalar and vector velocity - Acceleration - Motion in two and three dimensions -

Velocity and mean velocity - Acceleration and mean acceleration - Projectile motion

- Uniform circular motion - Relative motion - Newton's laws - Forces - Mass -

Applications of Newton's laws - Kinetic energy and work - Power - Potential energy -

Conservative forces - Work done by non-conservative forces - Conservation of

energy

System mechanics and rigid body mechanics:

Particle systems - Centre of mass - Newton's second law for a particle system -

Momentum of a particle system - Conservation of momentum - - External forces

and internal energy changes - Collisions - Impulse and momentum - Elastic

collisions in one dimension - Inelastic collisions in one dimension - Rotation -

Rotational variables - Rotation with constant angular acceleration - Linear and

angular variables - Rotational kinetic energy - Moment of inertia - Moment of a force

- Work, power and work-kinetic energy theorem - Rolling - Angular momentum -

Conservation of angular momentum

Fluid mechanics - Waves in elastic media

Fluids - Density and pressure - Fluids at rest - Measurement of pressure - Pascal's

law - Archimedean principle - Ideal fluids in motion - Streamlines and continuity

equation - Bernoulli equation - Oscillations - Simple, damped and forced harmonic motion, Pendulums - Resonance - Waves -

Transverse and longitudinal waves - Wavelength and frequency - Speed of a

moving wave - Energy and power of a moving wave - The superposition principle -

Interference - Phase vectors - Stationary waves and resonance - Acoustic waves -

Speed of sound - Interference - Sound intensity and level - Sources of musical

sounds - Beats - Doppler effect

Gravitation:

Newton's law of gravitation - Inertial mass and gravitational mass - Terrestrial

gravitation: the weight of bodies and the fall of bodies - Kepler's laws of planetary

motion - Gravitational potential energy - Artificial satellites and interplanetary probes

- Gravitation, astrophysics and cosmology

Heat and temperature:

Thermal equilibrium and zeroth law of thermodynamics - Temperature and heat -

Temperature measurement and temperature scales - Thermal expansion - Heat

capacity and specific heat - Changes of state and latent heat - Propagation of heat

The first law of thermodynamics:

Heat and work - Thermodynamic system - Internal energy - Thermodynamic

transformations - Reversible and irreversible processes - Graphical representation

of a transformation - Gas as a thermodynamic system - Work of pressure forces -

Molar specific heat at constant volume and at constant pressure - Ideal gas law -

Real gases and van der Waals equation - The first law of thermodynamics - Heat,

work and internal energy in the thermodynamic processes of the ideal gas:

isothermal, isobaric, isochoric and adiabatic.

The second law of thermodynamics:

Operation of heat engines - Reversible engines and the Carnot cycle - Irreversibility

of thermal processes - The second law of thermodynamics in the Kelvin and

Clausius formulations - Efficiency of heat engines - Absolute thermodynamic

temperature and efficiency of the Carnot cycle - Refrigerators - The entropy function

- Entropy changes in reversible and irreversible thermodynamic processes - Entropy

and heat engines - Natural processes and energy degradation.

Kinetic theory of gases:

Ideal gas model - Mean free path - Distribution of molecular velocities - Kineticmolecular

interpretation of the pressure and temperature of a gas - Internal energy

and equipartition principle - Molar specific heats of an ideal gas - Statistical

interpretation of the second law of thermodynamics - Entropy and probability:

disorder and information.

The electric field:

Introduction to electrostatics - Electric charges - Conducting and insulating materials

- Coulomb's law - Electric force and electric field generated by

## Recommended readings

Complete notes of the teacher corresponding to what presented in the lectures are available online.

Other texts suggested:

D.C. Giancoli: Fisica, principi e applicazioni, CEA

A. Giambattista: Fisica Generale. Principi e applicazioni, Mc-Graw Hill

J.S.Walker, Fondamenti di Fisica, Zanichelli

## Teaching methods

Traditional lecture with numerous exercises, targeted to geo / natural / environmental applications.

During the lessons. applications of physics to everyday situations will be constantly referred and situations of the "Nature" will be proposed to be interpreted on the basis of simple physical principles, stimulating synthesis capacity, simplification of the problems and suggesting analogies and correspondences to find the laws of physics in different areas.

Particular attention is paid to exercises with the involvement of the students. Additional Teachers contribute to the support of exercises.

## Assessment methods and criteria

The degree of learning is continually assessed during the course with the involvement of the students in exercises and questions.

At the end of the course a written test on some simple exercises is needed for admission to the oral test.

In the written test, carried out on types of exercises already discussed and developed during lessons, one want to check the simplification capabilities of the problems and a minimum capacity of calculation (with proper use of significant digits). It is also intended to evaluate the ability to correctly apply laws and principles with correct units.

The written test is passed if it is correct over a minimum threshold to be defined before the test. In this case, the written exam entitles to support the oral examination.

The oral exam aims to test the understanding of the laws, principles, links between subjects, the correlation between seemingly different situations. The aim is to assess the ability to apply the knowledge acquired during the course and not to be a mere enunciation. It also seeks to establish the accuracy and precision of the terms used not only in the enunciation of the physical laws but also in the description of the phenomena. In addition to the evaluation of an acceptable level of knowledge of Physics, one wants to evaluate the ability to independently develop solutions, to distinguish the essential from negligible.

The test is passed sufficiently according to rules widely announced during the course.

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## Other informations

The exercises are targeted at naturalistic, environmental and geological applications