The CrickSAT Mission

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The CrickSAT Mission

• Making connections with math and basic
  electricity, and electronics

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Why is math important?

• Read the article Math Mistakes in History The
  Mars Climate Orbiter http//threesixty360.wordp
  ress.com/2007/11/14/math-mistakes-in-history-the-m
  ars-climate-orbiter/
• Explain what went wrong with the Mars Climate
  Orbiter.

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On 9/23/On 9/23/99, 125,000,000 Mars Climate
Orbiter entered Mars atmosphere 100 km lower
than planned and was destroyed by heat. 99,
125,000,000 Mars Climate Orbiter entered Mars
atmosphere 100 km lower than planned and was
destroyed by heat.
1 lb 4.45 N
This is going to be the cautionary tale that
will be embedded into introduction to the metric
system in elementary school, high school, and
college science courses till the end of time.
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What is scientific Notation?

• Scientific notation is a way of expressing really
  big numbers or really small numbers.
• It is most often used in scientific
  calculations where the analysis must be very
  precise.

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Why use scientific notation?

• For very large and very small numbers, these
  numbers can be converted into scientific notation
  to express them in a more concise form.
• Numbers expressed in scientific notation can be
  used in a computation with far greater ease.
• Mass of Proton
• .00000000000000000000000167 grams
• Number of electrons passing by a point in a
  circuit
• 6250000000000000000 electrons per second

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Scientific notation consists of two parts

• A number between 1 and 10
• A power of 10
• N x 10x
• Are the following in scientific notation?

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Changing standard form to scientific notation.
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To change standard form to scientific notation

• Place the decimal point so that there is one
  non-zero digit to the left of the decimal point.
• Count the number of decimal places the decimal
  point has moved from the original number. This
  will be the exponent on the 10.
• If the original number was less than 1, then the
  exponent is negative. If the original number was
  greater than 1, then the exponent is positive.

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Example 1

• Given 289,800,000
• Use 2.898 (moved 8 places)
• Answer 2.898 x 108

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Example 2

• Given 0.000567
• Use 5.67 (moved 4 places)
• Answer 5.67 x 10-4

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Practice

• Use the link below to practice converting
  standard form to scientific notation.
• Converting to Scientific Notation

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Changing scientific notation to standard form.
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To change scientific notation to standard form

• Simply move the decimal point to the right for
  positive exponent 10.
• Move the decimal point to the left for negative
  exponent 10.
• (Use zeros to fill in places.)

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Example 3

• Given 5.093 x 106
• Answer 5,093,000 (moved 6 places to the right)

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Example 4

• Given 1.976 x 10-4
• Answer 0.0001976 (moved 4 places to the left)

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Practice

• Use the link below to practice converting
  scientific notation to standard form.
• Converting to Standard Form

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Even More Practice

• Below is a list of links to games and activities
  all having to do with scientific notation.
• http//www.aaamath.com/dec71i-dec2sci.html
• http//janus.astro.umd.edu/cgi-bin/astro/scinote.p
  l
• http//www.sciencejoywagon.com/physicszone/lesson/
  00genral/dectosci.htm

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Now take the quiz to test your scientific
notation skills!

• Click on the link below to take the quiz and then
  use the answer key for the correct answers.
• Quiz
• Answers

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Metric Prefixes
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Metric Prefixes
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I can rearrange equations to solve equations for
specified variables.

• What is the equation for solving for speed?
• Can you rearrange the equation to find distance?
• Can you rearrange the equation to find time?

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The CrickSAT Mission

• Reflection Write a reflection paragraph that
  includes your understanding of the following
  questions.
• The CrickSAT Mission data analysis relies upon
  your ability to collect the data, put into its
  appropriate forms and to calibrate the
  information correctly. Based upon what you have
  learned about basic math in the first lesson,
  explain the importance of being able to calculate
  and use basic mathematics correctly.
• End of Importance of Math Basics

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Connecting Satellites and Electronics

• All you need to be an inventor is a good
  imagination and a pile of junk.
• -Thomas Edison

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To understand electronics we must review basic
electricity. What is
Electricity?

• Everything is made of atoms
• There are 118 elements, an atom is a single part
  of an element
• Atom consists of electrons, protons, and neutrons

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• Electrons (- charge) are attracted to protons (
  charge), this holds the atom together
• Some materials have strong attraction and refuse
  to loss electrons, these are called insulators
  (air, glass, rubber, most plastics)
• Some materials have weak attractions and allow
  electrons to be lost, these are called conductors
  (copper, silver, gold, aluminum)
• Electrons can be made to move from one atom to
  another, this is called a current of electricity.

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• Surplus of electrons is called a negative charge
  (-). A shortage of electrons is called a positive
  charge ().
• A battery provides a surplus of electrons by
  chemical reaction.
• By connecting a conductor from the positive
  terminal to negative terminal electrons will flow.

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In your CricketSAT Mission Notebook In the
Electronics Tab Create a Table to organize the
variables and specific characteristics of each.
Always put your name and date at the top of your
table.
Quantity Resistance Current Voltage
Definition
Symbol/variable
equation
Unit of measure
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How you should be thinking about electric
circuits
Voltage a force that pushes the current through
the circuit (in this picture it would be
equivalent to gravity)
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Voltage

• A battery positive terminal () and a negative
  terminal (-). The difference in charge between
  each terminal is the potential energy the battery
  can provide. This is labeled in units of volts.
• Water Analogy

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How you should be thinking about electric
circuits

Current the actual substance that is flowing
through the wires of the circuit (electrons!)
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Current

• Uniform flow of electrons thru a circuit is
  called current.

WILL USE CONVENTIONAL FLOW NOTATION ON ALL
SCHEMATICS
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How you should be thinking about electric
circuits
Resistance friction that impedes flow of current
through the circuit (rocks in the river)
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Resistance

• All materials have a resistance that is dependent
  on cross-sectional area, material type and
  temperature.
• A resistor dissipates power in the form of heat

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Ohms Law
I V / R
I Current (Amperes) (amps) V Voltage
(Volts) R Resistance (ohms)
Georg Simon Ohm (1787-1854)
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Ohms law

• defines the relationship between voltage,
  current and resistance.
• These basic electrical units apply to direct
  current, or alternating current.
• Ohms Law is the foundation of electronics and
  electricity.
• This formula is used extensively by electricians.
  
• Without a thorough understanding of Ohms Law
  an electrician can not design or troubleshoot
  even the simplest of electronic or electrical
  circuits.
• Ohm established in the late 1820s that if a
  voltage was applied to a resistance then current
  would flow and then power would be consumed.

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Ohm's law magic triangle
Resistance R
Voltage E or V
Current I
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Ohms Law
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If you know E and I, and wish to determine R,
just eliminate R from the picture and see what's
left
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If you know E and R, and wish to determine I,
eliminate I and see what's left
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if you know I and R, and wish to determine E,
eliminate E and see what's left
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The force or pressure behind electricity
variable
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Symbol and Unit
O Ohm
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milliamp or just mA
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Conversions of units

• As a milliampere (milliamp or just mA) is
  1/1000th of an ampere, we can convert mA to Amps
  by just dividing by 1000. Another way is to take
  the current in mA and move the decimal to the
  left three places to accomplish the division by
  1000. Here's the scoop
• 275 mA / 1000 0.275 Amps
• Note that the decimal in 275 is to the right of
  the 5, and it's written as 275.0 (with a 0 added
  to show where the decimal is). Moving the decimal
  to the left three places gets up to .275 Amps,
  but we usually hang a 0 in front of the decimal.
• To convert Amps to milliAmps, just multiply by
  1000 or move the decimal to the right three
  places. Just the opposite of what we did here to
  convert the other way.

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Power
Definition
Variable
Equation
unit
Depends on
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Electrical Power

• Power is the rate of using or supplying energy
• Power  Energy  / Time   
• Power is measured in watts (W)Energy is measured
  in joules (J)Time is measured in seconds (s)  

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Electrical Power

• Electronics is mostly concerned with small
  quantities of power, so the power is often
  measured in milliwatts (mW), 1mW  0.001W.
• For example an LED uses about 40mW and a bleeper
  uses about 100mW, even a lamp such as a torch
  bulb only uses about 1W.
• The typical power used in mains electrical
  circuits is much larger, so this power may be
  measured in kilowatts (kW), 1kW  1000W. For
  example a typical mains lamp uses 60W and a
  kettle uses about 3kW.

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Electrical Power

• Besides this basic equation for power
• P IV
• remember we also have Ohms Law
• V IR .
• Challenge Based upon the two equations, how is
  power related to resistance?

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Power
Definition
Variable
Equation
unit
Depends on
Power is the rate of using or supplying energy
P
Power  Energy time
Power is measured in watts (W)Energy is measured
in joules (J)Time is measured in seconds (s)
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Variable
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Unit
O Ohm
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ELECTRICAL CIRCUITS
S.MORRIS 2006
More free powerpoints at www.worldofteaching.com
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• Activity Sheet should include your name, date,
  and the following discovery information as well
  as you data table and conclusion. Put in your
  Mission note book under the Electronics Tab.
• Discovery Activity Open and Closed Circuits
• Purpose Evaluate and create an open and a closed
  circuit.
• Materials Mini light bulb, connecting wire,
  battery
• Prediction Make a prediction of what an open
  and a closed circuit would be.
• Procedure
• Read all of the directions. Create a data table
  to record your results. Include draws and
  explanations.
• Manipulate the materials in many different ways
  to light the light bulb. Be sure to draw and
  explain each trial on your data table.
• Conclusion Review and analyze your data
  collected from the discovery activity. Write a
  conclusion, What is an open and closed circuit.

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Would This Work?
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Would This Work?
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Would This Work?
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The Central Concept Closed Circuit
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circuit diagram
Scientists usually draw electric circuits using
symbols
cell
switch
lamp
wires
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Simple Circuits

• Series circuit
• All in a row
• 1 path for electricity
• 1 light goes out and the circuit is broken
• Parallel circuit
• Many paths for electricity
• 1 light goes out and the others stay on

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Series and Parallel Circuit Activity

• Create an Activity Sheet for the following
  activity.
• Purpose Describe what happens to the current in
  a series as more resistors are added to the
  circuit.
• Prediction Predict what will happen to the
  current in a series as more resistors are added.
• Procedure Read all of the directions and create
  a data table to organize the information.
  Include drawings in your table.
• Materials 6 V battery, 3 light bulbs (Christmas
  lights will work), 6 connector wires

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Part 1 Series Circuit

• 1. Connect one bulb to the battery creating a
  closed circuit. Record the relative brightness
  and draw the circuit.
• 2. Repeat step 1 and add a second light. Record
  and draw.
• 3. Repeat step 2 and add a third light. Record
  and draw.
• 4. Remove the middle light. What happened?
• 5. Conclusion Write a statement which decribes
  what happens to the current in a series circuit
  as you add more resistors (lights)?

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1
2
3
The current decreases because the resistance
increases. Ohms Law says that IV/R. The
voltage in the system is constant, resistance
increases.
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PARALLEL CIRCUIT

• Place two bulbs in parallel. What do you notice
  about the brightness of the bulbs?
• Add a third light bulb in the circuit. What do
  you notice about the brightness of the bulbs?
• Remove the middle bulb from the circuit. What
  happened?

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The CrickSAT Mission

• Reflection Write a reflection paragraph that
  includes your understanding of the following
  questions.
• What connections can you make between Ohms Law
  and The CrickSAT Project? (purpose,
  importance,???)