Introductory Physics for Science Students

General Physics Module Overview

• This module is designed to provide students with a strong understanding of physics and its relevance to science, technology, and engineering
• Utilizes mathematics and develops problem-solving abilities
• It prepares students to know the applications of physics in multidisciplinary fields at the forefront of 21st-century technology
• Relevant to agricultural, archeological, health, medical, earth, space sciences, electronics, electromagnetism, communication tech, and energy systems requiring a solid physics foundation
• The module is designed for an introductory undergraduate level audience of science students
• The goal is to give an overview of physics based analysis and dating techniques used in science and technology
• High school mathematics and physics knowledge are prerequisites
• Physics laws, principles, and methods are explored in a descriptive manner using simple mathematics
• The course includes: preliminaries, mechanics, fluid mechanics, electromagnetism, electronics, thermodynamics, oscillations, waves, and applications in different science and technology areas
• Includes 10 experiments related to Mechanics, Electricity and Magnetism, and Electronics

Experiments in Mechanics

• Measurements of basic constants, length, mass and time
• Free fall
• Hook’s law
• Density of liquids
• Simple pendulum

Experiments in Electricity and Magnetism

• Calibration of voltmeter and ammeter from galvanometer
• Ohm’s law, parallel and series combination of resistors

Experiments in Electronics

• V-I (voltage-current) characteristics of diode
• Rectification
• Logic gate
• A minimum of six experiments should be performed
• Simulation experiments from the Internet can be used to supplement laboratory activities
• Experiment manuals will be prepared at each relevant university
• Each lab session should have between 25 and 30 students

Module Objectives after completion

• Review preparatory physics concepts for advanced physics courses
• Explain the kinematics and dynamics of particles in one and two dimensions
• State principles of fluids in equilibrium; solve problems using Pascal‘s, Archimedes‘s, and Bernoulli‘s principles
• Explain basic concepts of charges, fields, and potentials
• Analyze DC and AC circuits; solve circuit problems
• Demonstrate the use of cells (batteries), resistors, generators, motors, and transformers
• Explain and apply the first law of thermodynamics for closed systems
• Discuss systems with simple harmonic motion
• Explain physics applications in different sciences and technology
• Apply/describe experimental techniques; grasp lab guidelines
• Develop laboratory skills

Chapter 1: Preliminaries

• Physics originates from the Greek word for ""nature""
• It is treated as the foundation for science
• Deals with matter-energy relationships
• Relies on accurate measurement of natural phenomena
• Is fundamental to engineering and technology development

Measurement

• Comparison of an unknown quantity to a known standard
• A unit is the standard quantity for measurement

Chapter 1 Goals

• Explain physics
• Describe SI base units
• Describe derived units
• Express quantities in SI units using metric prefixes
• Describe relationships among models, theories, and laws
• Know physics quantity units
• Become familiar with prefixes
• Solve problems with unit conversion (dimensional analysis)
• Understand uncertainty and significant figures

Physical Quantities and Measurements

• Physical quantity: A quantifiable or assignable property of phenomenon or body, like length or mass
• Measurement: Comparison of a physical quantity with a standard
• Scientists may create new physical quantities
• Some quantities have fundamental importance
• Basic Physical Quantities: Quantities that cannot be expressed in terms of other physical quantities e.g., length, mass, and time
• Derived Physical Quantities: Quantities expressed in terms of fundamental quantities e.g., area, volume, and density

Physical value for equations

• Enable deep analyses of nature
• Require standard units
• Reveals simplicity in physical quantities in meters, kilograms and seconds
• Only seven basic physical quantities exist

Defining a Physical Quantity

• Defined by measurement method
• Defined by stating how it is calculated from other measurement e.g., define distance and time by using a stick and a watch
• Average speed defines total travel distance, divided by travel time

Units standardization

• Measurements use standardized units
• The length of a race is a physical quantity, expressible in meters (sprinters) or kilometers (distance runners)
• Units improve scientific expression and comparison of values

SI Units

• It is an abbreviation for International System of Units
• SI is a modern metric system
• SI was agreed upon at the eleventh International Conference of Weights and Measures in 1960
• Adopted worldwide as the main system of units
• The system is logically superior
• Based on 7 base quantities and their units

Conversion of Units

• Measurements use standardized units and to convert, you multiply by conversion factors to cancel unwanted units, to end up with desired units

Uncertainty in Measurement and Significant Digits

• Measurements are always uncertain
• Perfect accuracy for measuring physical quantities cant be achieve
• Knowing likely deviation is important
• Uncertainty analysis estimates deviations
• Uncertainty defines the range of possible values, and that covers true values, characterizing spread of measurement results Interval of possible values, usually includes confidence level
• Indicated the level of doubt

Measurement Errors

• Systematic Error: Results from mis-calibrated devices, consistently too small or large, eliminated by pre-calibrating againts standard
• Random Error: Results from varying measurements around the average, equally probable of being too large or small, results from scale division fineness
• Physics: Empirical science with measurements and calculations
• Analyze with uncertainties
• Systematic errors are generally simple to analyze but random ones require careful statistical analysis.

Measurement Thumb Rules

• Uncertainty in Scale: Measuring device equals smallest increment divided by two
• Example: Meter stick
• Uncertainty in Digital Device: Equals smallest increment
• Example: Digital balance readings 5.7513kg

Stating uncertainty

• The stating of uncertainty should allow no ambiguity
• Unstated uncertainty still implies
• Measuring 5.7cm implies between 5.65cm and 5.75cm with 0.05cm uncertainty
• Common rule to make 1/2 unit of last decimal place to obtain uncertainty
• Generic preferred form: Measurement = xbest±

Significant Digits

• The implied error in a recorded measurement is shown by the digits
• Writing an object length 0.428m implies 0.0001m uncertainty
• Should only report as many digits as consistent with error
• 0.428m has three significant digits, which is not influenced by number of decimal places
• 42.8cm is still only three significant figures
• Accepted only report one uncertain digit, meaning 0.02 report as 0.43 plus or minus 0.02; Not 0.428 plus or minus 0.02

Significant Zero Rules

• If the zero has a non-zero digit to the left then its significant
• 5.00 has 3 significant zeros, 0.0005 has only one
• 1.0005 has 5 significant zeros
• 300 undefined, should go like, 3 x 10, ones significant figure or 3.00 x 102, 3 significant zeros
• Zeroes only for location ARE NOT significant
• 0.0062cm - 2 significant figures
• 4.05cm - 5 significant figures

Rules For Significant Digits

• Multiplication/division uses same digits as the least factor
  • 45 divided by (3.22. x 2.005 m) = 6.97015 N/m^2
    • 4 is the least so its 7.0 N/m^2
• Addition or subtraction, equal the fewest decimal places of any term
  • 8.65cm + 8.4cm - 2.89cm = 15.16cm
    • Least precise is 8.4 cm, must stay in tenths, then its 15.2cm
• Area plate of 8.71cm, by 3.2cm
  • Answer should be in 27.87cm

Significant Figures

• Non-zero digits are significant
• Zeros within a number are significant
• Placeholders aren't significant - 0.000098 or 0.98 contain two significant figures
• Not to hold decimal place are, 4.00, or 4.65, and is not the same as requiring

Vectors, composition and resolution

• A scalar is a quantity with a number and unit, with magnitude but no direction which obeys ordinary algebra (mass, time, volume, speed)
• A vector is a quantity, specified by magnitude and direction with vector algebra (displacement, velocity acceleration, momentum)

Vector Representation

• Algebraic Method
  • Letters (or symbol) Velocity by ù, momentum by p
  • Magnitude by vector is always + scalar |A| or A
• Geometric Method
  • Vectors are straight arrows
  • Zero has 0 length point
• Vector Length: Magnitude with bigger arrow indicating larger magnitude
  • Vectors can be transported parallel
  • Beginning has to attach to add vectors end to of another to arrow
  • A vector will changes when magnitudes change, direction or both

Physical quantities

• Same units or same characters
• Vectors maybe multiped by a number or scalar
• Multiplication by pure number will change the magnitude of the vector, so If its - then direction in negative
• The new vector, also becomes a force when it is multiped by the scalar, so the direction will change

Vector Addition Rules

• A vector resulting from combining two vectors, using methods that follow

Graphical method of vector addition

• head to tail in any order
• vector drawn from tail of the first vector to the head of the last vector

Parallelogram Law of Vector Addition

• States resulting sum of R of two vectors A and B
• Diagonal of parallelogram for which two vectors A and B becomes adjacent sides

Three Concurrent Vectors: A, B, R

• A, B also called components of R
• Magnitude of diagonal is resultant, the direction comes from cosine/sine laws
• applying cosine and sine laws for triangle formed by 2 vectors

Components of Vector

• To find trig values and functions apply sine and cos
• The functions can be added together with results

Pythagoras theorum.

• The resulting equation is solved for a using pythag