Science 9: Electricity

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Transcript Science 9: Electricity

Science 9: Electricity
Static Charge
Big Idea: Static charge is produced by electron transfer.
Model charging using (+,-) diagrams.
Science 9: Electricity
Laws of Static Charge
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Opposite charges attract
Like charges repel
Neutral objects are attracted to charged objects
Demos:
 Scotch Tape
 Vinyl and Clear Plastic Strips
Simulations:
PhET
 John Travoltage
 Balloons and Static Electricity
Science 9: Electricity
Electric Potential, Current, Resistance, and Energy
Potential Energy vs Potential Difference
Analogy:
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Climbing Stairs
Demo:
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Van de Graaff generator
and voltmeter
Science 9: Electricity
Electric Potential, Current, Resistance, and Energy
Current and Energy Transfer in a Circuit
Analogy:
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Water Slides
Science 9: Electricity
Electric Potential, Current, Resistance, and Energy
Resistance
Big Ideas:
Slows Current
Transforms Electric Energy into other forms
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Ohm’s Law calculations:
V = IR
 I = V/R
 R = V/I
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Science 9: Electricity
Series and Parallel Circuits
Big Ideas:
Series
 Current remains constant
 Voltage changes (Vlost =Vgained)
 Resistance increases
Parallel
 Current changes (Iin = Iout)
 Voltage is the same
 Resistance decreases
Simulations: PhET
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Circuit Construction Kit
Science 9: Electricity
Electric Power
Big Idea:
Rate at which electrical energy is transformed.
For a load:
 Greater the power rating
 More current
 Less resistance
Calculations:
P = VI
E = Pt
Science 10: Motion
An Introductory activity, for this unit, is
important!
Allows students to “draw” on previous learning.
Suggestions:
 Think Fast Activity page 341 BC Sc10
 Jumping off a table
 Knees bent
 Locked knees
 Different heights
 Many others …
Science 10: Motion
Uniform Motion
Big Idea: Equal displacements in equal time intervals.
Battery powered cars are very valuable.
Science 10: Motion
Uniform Motion
Vectors
 Magnitude and a direction
 Opposite directions have opposite signs
 Must be able to find the “change in” a vector quantity
Science 10: Motion
Uniform Motion
The Position-time Graph
 Straight line
 Interpret motion using the graph.
Demo: Motion Sensor and software
Science 10: Motion
Uniform Motion
The Position-time Graph
 Calculating Slope
Science 10: Motion
Uniform Motion
Calculating Slope
Science 10: Motion
Uniform Motion
Calculating Slope: 1. Choose two points on the graph
Science 10: Motion
Uniform Motion
Calculating Slope: 2. Draw a right triangle
Science 10: Motion
Uniform Motion
Calculating Slope: 3. Use the axes to measure rise & run
Science 10: Motion
Uniform Motion
Calculating Slope: 3. Use the axes to measure rise & run
8 m [forward]
4s
Science 10: Motion
Uniform Motion
Calculating Slope: 4. slope = rise/run
8 m [forward]
4s
Slope = 2 m/s [forward]
Science 10: Motion
Uniform Motion
Calculating Average Velocity
Vav = Δd/ Δt
Δd = (Vav)(Δt)
Δt = Δd/ Vav
Science 10: Motion
Uniform Motion
Simulation:
This PhET simulation can be used throughout this unit.
The Moving Man
Science 10: Motion
Acceleration (non-uniform motion)
The Rate of Change in Velocity
Big Idea:
How quickly you change your velocity (Δt ) and the
magnitude of change in velocity are both factors in an
object’s acceleration.
Eg. Having a smaller change in velocity and
increasing the time to change velocity decreases the
acceleration.
Science 10: Motion
Acceleration (non-uniform motion)
 Velocity-time graphs best represent non-uniform motion.
 Interpreting Velocity-time graphs
Science 10: Motion
Acceleration (non-uniform motion)
The slope of a velocity-time graph is average
acceleration.
Calculating slopes
Science 10: Motion
Acceleration (non-uniform motion)
Calculating Acceleration
Science 10: Motion
Acceleration (non-uniform motion)
Acceleration Due to Gravity
Science 10: Motion
Acceleration (non-uniform motion)
Simulations
PhET
 The Moving Man
 The Maze Game