Spicy physics
Aleš Mohorič, Sergej Faletič
Faculty of mathematics and physics
University of Ljubljana
Faculty of mathematics and physics
University of Ljubljana
Recipe to improve physics teaching:
• knowledge.........a lot
• enthusiasm........planty
• ICT.....................teaspoon (as a spice)
Examples of ICT use:
• personal respond system (PRS or “clickers”)
• electronic sensors with computer interface
• e-learning portal www.nauk.si
PERSONAL RESPONSE
SYSTEM
“CLICKERS”
Familiar?
me, me...
her, her...
Solution?
Brief, multiple-choice questions
Immediate analysis by electronic responders
Basic rules in clicker use
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explain the procedure
explain the handling with clickers
emphasize the anonymity of responses
activity begins with an experimental question
read the question aloud before seting up the timer
the display shows a histogram of responses
Purpose of questions
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test existing knowledge
verify the effectiveness of homework
test recall of lecture point
choose the next step in a complex calculation
reveal pre-existing perception
check conceptual understanding
use of the concepts in a new context
predict the results of the experiments, simulations, video, etc..
compare various representations (graphical, mathematical,
...)
Procedure
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question
vote
peer discussion
vote
whole-class discussion
Basic rules in clicker use
• do not reveal the correct answer
• if the majority of students chose the correct answer,
volunteer explains the correct answer and why other
are wrong
• for uneven distribution of responses, the students
discuss the question in pairs, after a few minutes,
repeat vote
• representatives of specific groups (in terms of
representation of responses) explain why they chose
the selected answer (it is better if we start with the
group who chose the wrong answer)
Basic rules in clicker use
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at the end tell which answer is correct
why is it correct (explanation)
why the other answers are incorrect
summarize the explanations of students
thus recognizing students and encourage them to
continue to participate in the discussion
• teachers should be sensitive and open to any
criticism that students give to each question
Poor use of clickers
• solely for taking attendance
• for quizzes or high-stakes testing
• only occasionally, or at set times
Better use of clickers
• integrated into lecture, frequent
• require or encourage peer instruction
• mix of difficulty
• generous credit for any answer
• low grade impact (~2%)
Poor Concept Tests
• merely test recall
• involve blind application of
formula/recipe
Calculate the current
in 2 ohm resistor and
• involve many numbers
potential difference
between P and Q
Better Concept Tests
• check qualitative understanding (no calculator)
• apply familiar skills in new contexts
• multiple questions to lead thru multi-step reasoning
• test a learning goal When S is closed, what happens to:
(a) intensities of A and B?
(b) intensity of C?
(c) current through battery?
(d) potential difference across
A, B, and C?
(e) the total power dissipated?
Some considerations
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too easy questions seen as a quiz (entertainment)
may mislead students for the test
challenging questions are most useful for learning
order is important: start easy, hard in the middle, end
easy
• 4-6 options for answer (min 3)
• the easiest way: google “ConcepTests”
(http://galileo.harvard.edu/
http://www.mines.edu/Academic/physics/classroomco
mmunicators/assets/banks.html.)
Technicalities
• infrared (IR) clickers are cheaper than the radio
frequency (RF) clickers
• IR performance (reception of responses, longer
minimum time between two receptions, range,
handles only up to 30 clickers) worse than RF
• clickers with alpha-numeric characters, (not
widespread)
• PRS is independent of presentation
• up to the user to map presentation to PRS
Examples
What is your age?
1) 10-20 yrs
2) 20-30yrs
3) 30-40 yrs
4) 40-50 yrs
5) 50-60 yrs
6) > 60 yrs
I have taken or taught a
class that used
clickers.
TRUE
FALSE
Examples
A box of mass m is held stationary against a vertical wall.
There is friction between the wall and the box. The direction
of the force of friction exerted on the box by the wall is...
(A) up
(B) down
(C) zero
(D) not enough information
given to answer the question.
Examples
A toy car with mass m moves along a massless wooden
plank lying horizontally over two support posts, as shown.
The car is rolling across the bridge from point P2 to point P3,
(left to right). What can you say about the magnitude of the
net torque (i.e. the sum of all torques) about the point P1?
(A) It is increasing.
(B) It is constant, and zero.
(C) It is decreasing.
(D) It is constant, and non-zero.
(E) Not enough information is given.
ACTIVITY:
Write a clicker question
• pick a concept or skill you think is important and/or
difficult for students.
• identify any common misconceptions to use as
distractors.
• write the question as simply and clearly as possible.
ACTIVITY:
Respond to histograms
B correct
A correct
A wrong
ELECTRONIC SENSORS
AND
COMPUTER INTERFACE
Vernier LabPro interface
data-collection system
- 4 analog channels, over 50
different sensors,
(temperature, dissolved
oxygen, gas pressure, pH,
force...)
- 2 digital channels (motion
detectors, photogates, radiation
monitors, rotary motion
sensors, and drop counters)
Accelerometers Barometer
Ion-Selective Electrodes Light Sensor
Blood Pressure Sensor
Magnetic Field Sensor
Charge Sensor
Microphone
CO2 Gas Sensor
Motion Detectors O2 Gas Sensor
Colorimeter
Ohaus Balances
Conductivity Probe
ORP Sensor
Current Probe
pH Sensors
High Current Sensor NEW
Photogate
Differential Voltage Probe
Power Amplifier NEW
Digital Control Unit
Digital Radiation Monitor
Dissolved Oxygen Probe
Relative Humidity Sensor
Drop Counter
Respiration Monitor Belt
Dual-Range Force Sensor
Rotary Motion Sensor
EKG Sensor
Salinity Sensor
Electrode Amplifier
Sound Level Meter
Flow Rate Sensor
Soil Moisture Sensor
Force Plate
Spectrometers
Gas Pressure Sensor
Spirometer
Vernier GPS Sensor NEW
Temperature Probes Thermocouple
Garmin® GPS Units
Turbidity Sensor
Gas Chromatograph NEW
UV Sensors
Hand Dynamometer
Voltage Probe
Hand-Grip Heart Rate Monitor Watts Up Pro NEW
Instrumentation Amplifier
Wireless Dynamics Sensor System
Technicalities
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Lab Pro interface, USB
Logger Pro software
one licence per school
sensors sold separately
Innovative uses
• high CO2 levels putting you to sleep?
• investigating periodic trends
• spectral analysis of fireflies
• how do you dim an LED?
• showing speed and location in Google maps
• test hearing response with labquest
• studying the diving reflex in the laboratory
http://www.vernier.com/innovate/index.html
ACTIVITY
motion detection / graphical representation
plot a graph x(t) or v(t) and try to repeat it!
E-LEARNING PORTAL
NAUK
www.nauk.si
e-learning portal www.nauk.si
GOALS:
• active students
• didactical
recommendations
• feedback
• fresh, everyday cases
• include measurements
Advantages
• adjust the level based on responses
• union of peer-instruction and self-learning
• simulation and playing based learning
Disadvantages
• disengaging the reality
• overuse of ICT saturates students
• e-learning is effective only for intro courses
Types of material
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multiple choice questions
context rich exercises
Multiple choice questions
• graphic material,
• real context,
• multilevel responses – hints/solutins
• adjustable number of repetitions
• record of succes rate
• variation of answers
• different answer modes
Context rich exercises
• central story with special cases
• modular composition
• graphic material
• real context,
• multilevel responses – hints/solutins
• “exploring the landscape”
• analysis of measurements
wrong
wrong
correct
...
end
Tools
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reading the graphs
measuring distances, angles
ploting lines, vectors, curves
sky map
linking...
Example
Odboj teniške in žonglerske žogice
http://www.nauk.si/materials/258/out/index.html#state=1
e-nauk
• open source
• do it yourself
• wiki type
syntax...
ACTIVITY
• write a multiple choice question
• write a scenario for a context rich
exercise