PEF102 - L1 - Introduction to Physics and Units of Measurement 1.pptx

PEF102 ELEMENTARY PHYSICS LECTURE NOTE 1 Introduction to Physics and Units of Measurement 1 PEF102-L1-20230821-v1  PREVIOUS LECTURE NOTE  Module Introduction 2 5502ICBTME-L3-20230726-v1 ...

PEF102 ELEMENTARY PHYSICS LECTURE NOTE 1 Introduction to Physics and Units of Measurement 1 PEF102-L1-20230821-v1  PREVIOUS LECTURE NOTE  Module Introduction 2 5502ICBTME-L3-20230726-v1  CONTENTS 1. What is Physics? 2. Units of Measurement 3. International System of Units (SI) 4. Imperial System of Units 5. Unit Conversions 3 PEF102-L1-20230821-v1  WHAT IS PHYSICS? 1/4  Fundamental of the sciences.  Explores matter and energy and their interaction.  Theoretical Physics: The development of theories and mathematics for the laws of physics  Applied Physics: The practical application of principles of Physics  Experimental Physics: The application of Physics theories to build and work scientific equipment. A mix of Physics and 4 Engineering. PEF102-L1-20230821-v1  WHAT IS PHYSICS? 2/4  There are several fields of Physics including,  Classical Mechanics – motion of bodies  Electricity and Magnetism  Quantum Mechanics – motion of small bodies  Optics – study of light  Acoustics – study of sound  Thermodynamics – study of heat  Solid-State Physics – study of solids  Plasma Physics – study of plasma  (Plasma is superheated matter – so hot that the electrons are ripped away from the atoms forming an ionized gas.)  Atomic, nuclear and particle physics – study of atoms 5  PEF102-L1-20230821-v1  WHAT IS PHYSICS? 3/4  A few contributors to Physics  Galileo Galilei – investigated about falling objects.  Issac Newton – established the three laws of motion.  Michael Faraday – introduced electromagnetic induction.  James Clerk Maxwell – published about the electromagnetic field. The 10 best physicists | Culture | The Guardian 20 Physicists Who Revolutionized Our Understandi ng of the World (businessinsider.com) 6 PEF102-L1-20230821-v1  WHAT IS PHYSICS? 4/4  Physics may cross over to other fields,  Astrophysics  Geophysics  Biophysics  Mathematical Physics  Engineering  A form of applied physics  Using physical laws to innovate solutions 7 PEF102-L1-20230821-v1  STANDARD NOTATION AND SIGNIFICANT FIGURES  Standard notation;  E.g., 45500 into standard notation  E.g., 0.000034 into standard notation  Significant figures;  E.g., How many significant figures does 4.5 have? 2  E.g., How many significant figures does 4 have? 1  E.g., How many significant figures does 0.03805 have? 4 More significant figures mean, more accuracy. Choose significant figures depending on 8 PEF102-L1-20230821-v1 POWERS OF 10 9 METRIX PREFIX 10  UNITS OF MEASUREMENT  Measurements are taken to connect a physical phenomenon to mathematical analysis.  They compare a physical quantity against an agreed upon standard and how many of these standard units are present.  E.g., the length of a ruler may be 30 cm. 1cm is standard unit. The ruler, when compared to this standard unit, is 30 times longer.  Clear definitions of physical units is needed for many applications including scientific studies, trade and commerce.  Base units: fundamental units, established from natural phenomenon, that may be used to derive a system of units. These units are not combinations of other units. E.g., cm or seconds. 11 PEF102-L1-20230821-v1  SYSTEM OF UNITS 1/2  There are several sets/systems of units used globally.  Main two system of units 1. Imperial System of units  Developed by England. Mainly, used by the USA, the UK and Canada.  Similar to the US customary units and English Engineering Units. 2. Metric System of units Mainly used in this module i. MKS system International System of Units  Meter, Kilogram and Second as base units. Majority of the world. ii. CGS system  Centimeter, Gram and Second as base units. 12 PEF102-L1-20230821-v1  SYSTEM OF UNITS 2/2 13 PEF102-L1-20230821-v1  INTERNATIONAL SYSTEM OF UNITS (SI) 1/5  International System of Units; SI units Système International d’unites.  MKS system with additional units are used as SI base units. 14 PEF102-L1-20230821-v1  INTERNATIONAL SYSTEM OF UNITS (SI) 2/5  Length  Time  Meter (m)  Second (s)  1m is defined as the distance light  60 seconds = 1 minutes, 60 travels in 1/299,792,458 seconds minutes = 1 hour, and 24 hours = 1 day.  Mass  Kilogram (kg)  Temperature  Mass ≠ Weight  Kelvin (K)  Acceleration due to gravity g =  Electric Current  Ampere (A) 15 PEF102-L1-20230821-v1  INTERNATIONAL SYSTEM OF UNITS (SI) 3/5  SI Derived Units: units derived by combining SI base units.  E.g., Measurement of angle  Angles are usually measured in degrees.  SI unit of angle is radian (rad).  Application: to find arc length.  is in radians. 16 PEF102-L1-20230821-v1  INTERNATIONAL SYSTEM OF UNITS (SI) 3/5 Other derived SI units 17 PEF102-L1-20230821-v1  INTERNATIONAL SYSTEM OF UNITS (SI) 5/5  Prefixes may be added or removed from beginning of the units.  E.g.,  kg is the only SI base unit with a prefix. 18 PEF102-L1-20230821-v1  IMPERIAL SYSTEM OF UNITS  Alike to United States Customary Units and British/English Engineering Units.  SI prefixes like kilo, mega and nano cannot be used with this system of units.  (Pounds-force)  (Pounds-mass) 19 PEF102-L1-20230821-v1  UNIT CONVERSIONS  E.g., Convert 7 feet to inches.  Steps: 1. Write unit conversion factor as a ratio. Ensure that units cancel out correctly. 2. Fill numbers in so that the numerator matches the denominator  Recall, 1ft = 12 in 20 PEF102-L1-20230821-v1  SUMMARY LO1: Understand Physics and Measurement.  Introduction to Physics and Units of Measurement 1 LO2: Understand the fundamentals and practical aspect of kinematics/ motion in one dimension LO3: Understand the fundamentals of Elementary Mechanics LO4: Understand the fundamentals of Electricity and Electromagnetism. LO5: Understand the basics of Thermodynamics. 21 5502ICBTME-L3-20230726-v1  NEXT LECTURE NOTE LO1: Understand Physics and Measurement.  Units of Measurement 2 and Quantities LO2: Understand the fundamentals and practical aspect of kinematics/ motion in one dimension LO3: Understand the fundamentals of Elementary Mechanics LO4: Understand the fundamentals of Electricity and Electromagnetism. LO5: Understand the basics of Thermodynamics. 22 PEF102-L1-20230821-v1  THANK YOU FOR LISTENING! PEF102-L1-20230821-v1