Course Review

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Course Review

• Read your Project Reports
• What did you do, how did you do any calculations,
  what units were involved and what were the
  conclusions
• Review the Studio and Lecture Quizzes
• Make sure you know how the answer was obtained.
  If it was conceptual be sure you understand the
  concept
• Reread the article references
• See the syllabus for the instruction given in the
  studio. This is important

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New Technology

• Who developed major technology
• Roughly when
• What is the application of this technology

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WEEK 1 Conservation of Energy

• Project on Solar Cells
• Different forms of energy
• Joules and watts
• Hypothesis, efficiency, averages, graphs
• Lecture
• Cost of electricity
• Energy conservation
• Entropy

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Every time forces triggered by the stored energy
make things move, we say that those forces do
work. Energy is therefore the capacity for doing
work in its broadest sense. Motion, heat,
electricity, magnetism, light, can be made to do
work, thus, they all embody different forms of
energy
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What is kWh ?
An appliance rated at 1 kilowatt (1 kilowatt
1,000 watts) consumes one kilo-joule of energy
(same as 1,000 joules) in every second.
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By the same token, the energy used by a
one-kilowatt appliance in one hour (called 1
kilowatt-hour), that is, 1 kilo-joule / second x
3,600 seconds, is 3,600 kilo-joules
Thus 1 kilowatt-hour 1 kilo-joule/second x
3,600 seconds 3,600 kilo-joules
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Law of conservation of energy
The conversions of energy are never
fully effective because some of the
energy becomes low grade (unusable) heat
However
Initial energy useful energy resulted
energy wasted
The total energy is conserved!
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The Law of Entropy
The natural processes lead to increase in
disorder
Natural processes are irreversible.
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WEEK 2 Direct comparison with a standard

• Project on Measurement, area, volume mass and
  density
• How to convert between units
• suffixes to denote very large or very small
  numbers
• significant figures
• No lecture

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TIME, MASS and LENGTH

• Time
• Fundamental unit is the second (USA and SI)
• Now measured by frequency of light
• Mass
• Fundamental unit is the kg (SI) or pound(USA)
• Still a chunk of metal
• Length
• Fundamental unit is m (SI) or yard (USA)
• Now measured by distance light travels

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WEEK 3 MEASUREMENT WHEN NO DIRECT COMPARISON IS
POSSIBLE

• Project- Measurements when you cant do a direct
  comparison with a standard
• Using ratios to measure height or length
• Measuring many items when one is too small
• Scientific notation
• Demonstration on finding the size of a molecule
• Lecture calibration standards

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Indirect Measurement
Rule height Object height
Ruler distance Object distance
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SCIENTIFIC NOTATION

• LARGE NUMBERS
• and small numbers
• 0.000000960 can be written as

2 significant figures
390,000,000,000,000,000,000,000 can be written
as
3.9 x 1023
3 significant figures
9.60 x 10 -7
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WEEK 4 HEAT TRANSFER

• Project cooling a cup of liquid
• Effect of cup material and starting temperature
• Temperature scales, ways of losing heat
• Lecture
• Materials of the ages, gold, bronze, iron
• Wood, glass, metals
• Ceramics, plastics, composites, superconductors

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All Things Known to a PHY107 Student

• Gold
• Bronze
• Iron and Steel
• Ceramics
• Plastics
• Composites
• Aerogels
• Superconductors

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WEEK 5 CHOOSING MATERIALS

• Project properties of elastic cords
• Effect of load, length and thickness
• Lecture 4
• Internal structure
• crystals
• Stress, strain, elastic constant
• Deformation

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• STRESS force applied per unit area
• STRAIN change in length
• original length
• ELASTIC MODULUS STRESS/STRAIN

The stiffer the material, the less the length
will change under same stress
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Graph of stress versus strain
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WEEK 6 REFLECTION and REFRACTION

• Project properties of light
• Names and locations of angles
• Refractive index and Snells law
• Total internal reflection
• Speed of light changes with material
• Lecture 5
• Properties of light, reflection, refraction,
  scattering
• Human vision and correcting defects

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VISIBLE LIGHT

• Small part of the electromagnetic spectrum
• Travels in straight line in same medium
• Can be reflected, refracted, scattered and
  absorbed
• Nothing can move faster than light in a vacuum
• Possesses energy

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(No Transcript)
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WEEK 7 USING LIGHT

• Project images and objects with lenses
• Magnification, distances and sizes
• Image properties
• Plane mirrors

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Focused image with a lens
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Image Formed by the Eye
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WEEK 8 COLOR and WAVELENGTH

• Project colors, light sources and filters
• Analysis of light, wavelengths, energy
• Color addition and color subtraction
• Use of spectrometer
• Properties of laser light
• Passing light through a prism
• Lecture 7
• Color by addition, subtraction and mixing
• Atoms as sources of light
• Wave and particle description of light
• Electrical circuits, series and parallel,
  batteries

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Color Addition
Light Sources
Color Subtraction
Paints and Filters
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Light from atoms

• Light is made up of little
• packets of energy called photons
• When you have many photons they
• behave as if they were a wave
• The photons are emitted by atoms

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WEEK 9 ELECTRICAL BATTERIES and CIRCUITS

• Project making and using batteries
• Effect of different battery components
• Parallel and series connections
• Measuring voltage and current
• Demonstrations on electrostatic charge
• Lecture 8
• Setting up circuits

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How a battery works
Cathode(-)
Anode()
Electrolyte
Positive ions
Insulating layer forms on anode
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CURRENT FLOW

• Current is the flow of electrons
• By convention we say positive current flows from
  the anode () to the cathode(-)
• At the microscopic level electrons (negatively
  charged) move from the cathode(-) to the anode()

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How to Measure Current and Voltage
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WEEK 10 ELECTRICITY and MAGNETISM

• Project electromagnet
• Effect of voltage, of turns
• Demonstration of motors, generators and the
  relation between electricity and magnetism
• Lecture 9 on different forms of electromagnetic
  radiation
• Radio, radar, heat (IR), visible, UV, X-rays
• applications

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WEEK 11 ELECTRICAL CIRCUITS

• Project
• Ohms law
• Resistance, voltage and current
• Lecture 10
• Development and use of computers, ENIAC
• Audion, transistor and integrated circuits
• Binary communications

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FirstTransistor
(1947, John Bardeen, William Shockley, Walter
Brattain at Bell Labs)
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Binary Uses in Computer

• Digital characters ASCII code
• Stored as a byte (8 binary digits)
• Example A 01000001
• Arithmetic with digital
• Example 01 10 11 which means
• 1 2 3 in decimal
• Computer code
• Instruction, what to do, where to do it, which
  piece of data to use

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WEEK 12 MOTION and TRANSPORT

• Project
• Constant speed and acceleration
• Potential energy and kinetic energy
• Gravity
• Lecture 11
• History of automobiles and planes
• Car engine cycle
• Mechanics of flight and propulsion

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DEFINITIONS FOR USE WITH MOTION SPEED is how
rapidly an object moves or changes its
position. It is calculated by dividing how far an
object moves by the time taken to move.
Speed (distance moved) / (time taken
moving) Example. If a runner covers 400m in 50
s, the average speed is 400m / 50 s 8
m/s ACCELERATION is how rapidly an object
changes its SPEED (or VELOCITY) It is calculated
by dividing the change in speed by the time taken
to make that change. Acceleration (change in
speed) / (time taken to make that
change) Example. A car accelerates from rest
(speed0 m/ s) to 28m/s in 7 s acceleration
(28 0) m/s / 7 s 4 m/s per second 4
m/s2 FORCE is what causes something to
accelerate. If some object changes its speed it
has accelerated and must have had a FORCE acting
on it. The larger the mass of an object the
smaller its acceleration for the same
FORCE. NEWTONS Law states that force is the
product of mass and acceleration. Force mass x
acceleration Example. A mass of 2 Kg changes its
speed from 5 m/s to 25 m/s in 2 s. Acceleration
(25-5)m/s / 2s 20m/s / 2s 10 m/s per s or
10 m/s2 Force 2 kg x 10 m/s2 20 Newtons
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GRAVITY is the FORCE by which an object is
attracted to the center of the Earth It is
calculated by multiplying the mass by the
gravitational constant(10 m/s2). Force (Newtons)
mass (in Kg) x 10 More precisely the
Gravitational constant is 9.81 m/s2 , rather than
10 m/ s2 POTENTIAL ENERGY(PE) is energy
possessed because of height. PE can also occur
by storing energy in springs, electric fields and
magnetic fields. PE(in Joules) mass(in Kg) x
gravitational constant x change in height(in
m) Example. Gain in PE by lifting 5 Kg up 2
meters is 5 x 10 x 2 Joules 100
Joules KINETIC ENERGY (KE) is energy possessed
because of the movement of an object. KE(Joules)
½ x mass(in Kg) x (speed)2 when speed is in
m/s Example. A mass of 5 Kg with a speed of 4
m/s has a KE ½ x 5 x 4 x 4 40
Joules MECHANICAL ENERGY is energy associated
with motion and position. It is calculated by
adding together the kinetic energy and the
potential energy.
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In the beginning--

• Charles Duryea 1895
• Ransom Olds 1901
• Henry Ford 1903
• 1908 the Model T

• 360 vs 5000

• 15 million by 1927

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The Secrets of Flight

• Birds

• Kites and Gliders

• Balloons and dirigibles

• Propeller Driven Planes, Wright bros.

• Jet Driven Planes

• Helicopters

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How a Balloon Works
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WEEK 13 ROCKETS and FLOTATION

• Project Flotation
• Archimedes principal
• Reduction in weight when submerged
• Lecture 12
• Rockets and rocket propulsion
• Balloons and dirigibles

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Buoyancy-Archimedes principle
A submerged object is pushed up with a force
equal to the weight of the water displaced
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Newtons Third Law of Motion
Newtons Third Law of Motion For every action
there is an equal and opposite reaction
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RocketMechanisms