DRAFT
PHYSICS VIDEO CONTENT
GUIDLINES
WITH
LAB EXPERIMENTS
1
INTRODUCTION TO PHYSICS VIDEOS
CONTENT
INTRODUCTION AND NOTE:
The main objective of these ten videos is to assist users to acquire the
knowledge , understanding , and application of essential concepts in Physics.
For this purpose, these videos should not only explain essential concepts and
theory but also, should, include practical demonstrations to enhance the
understanding and application of Physics.
Videos include experiments, should allow a fine combination of theory and
hands on application of concepts, as these videos can be used to develop skills
for the actual experiments in school labs.
The goal is that these videos should transfer essential practical skill and good
understanding of theoretical concepts in Physics.
The format below should be considered for the each video.
MAIN TOPIC:
SUB TOPICS: (Should cover essential theory topics)
Everyday Applications:
Essential Content:
Practical Examples/Demonstrations:
Purpose/Application/Theory
Apparatus/Equipment required
Proper use of equipment (Demonstrate)
Precautions/Safety Measures
For lab experiments also to include procedures and errors of measurements.
Results/End Products
Discussion/Conclusion
Examples of trends in Technology/New Technologies and
Innovations
Summary of important concepts
Assessment of skills learnt
( Short Quiz, interactive questions/answers)
2
NOTES:
The intention for developing the outlines for the content and support material
for videos is not to provide the transcript but to provide guidelines for
essential content of the videos. Even though practical examples have been
given in the guidelines, these should not block the creativity of video
producers to add examples and illustrations and meet the necessary terms of
reference for production. The first five video contents should guide the
approach being considered. Further where applicable, the content of videos
could be arranged such as to best fit the needs of the users, and intended
application of the videos. In order to enhance / improve the content of a
given video, CXC syllabus is a useful guide. Even though the following video
guidelines contain samples of theory, but where required, additional examples
and theory be added to cover the sub topics of each video.
Apart from using the Subject Specialist to assist script writing, the producers
should hire the individuals with technical and practical skills in order to
create quality output.
VIDEO 1
MAIN TOPIC: Measurements
SUB TOPICS AND THOERY TO COVER:
Length, Area, Volume
Standard Units in Measurements.
Examples of standard and derived units
Errors of Measurements in Instruments
Experiments: Measurement of volume of regular and irregular objects
INTRODUCE UNITS:
The International System of Units (SI units) and advantages of using these units.
EVERYDAY APPLICATIONS
Some Examples: (Illustrate using pictures)
3
Length:
Area:
Volume:
Length of the laboratory bench, height of a student
Area of a double bed, area of the classroom floor
Liquids sold in a supermarket are usually measured in litres or millilitres.
For example a 2- litre bottle of juice, a 1- litre bottle of milk, a 15 ml bottle of eye
drops.
Sample theory -Measuring Instruments and Errors: Some examples.
Standard instruments used in determining length, area and volume (e.g. rulers, tape measure,
vernier caliper, micrometer screw gauge, measuring cylinder, burette, etc). (Illustrate using
pictures)
Discussion of errors associated with the use of these instruments e.g. zero error, parallax
error, calibration error.
EXPERIMENT # 1 –
Measuring Volume
MAIN OBJECTIVES
1. The use of the vernier and the displacement can to measure volume of regular and
irregular objects.
2. Understanding the errors associated with the measurements
4
VERNIER
The vernier is an instrument that is used to measure the length, width and diameter of an object.
Volume is the amount of space an object occupies.
For a regular object such as a cube or a sphere, the volume can be determined using standard
formulas.
For an irregular object, that is an object with no definite shape, the volume is measured using the
displacement method. When an object is placed in a fluid, it occupies space and therefore
displaces the liquid.. The volume of the liquid displaced is equal to the volume of the object.
Apparatus:
Measuring cylinder (25 ml or smaller for better accuracy )
Water
Vernier
Metal bob
Wooden block
Eureka / displacement can
Stone
5
PROCEDURE (a) DIRECT MEASUREMENT:
Using the vernier
•
•
•
•
Ensure there is no zero error on the vernier. If there is an error, record the reading.
Measure the diameter of the bob using the vernier.
Repeat twice, changing the orientation of the bob in each case.
Record your results in Fig. 1.
Reading #
Diameter of Bob (cm)
1
2
3
Mean/Average
Fig 1
•
•
Find the mean/average diameter D. The radius r, of the bob is D/2 in centimeters.
Calculate the volume of the bob using the formula [Volume of a cube = 4/3 πr3 ]
PROCEDURE (b) -DISPLACEMENT METHOD
(Using displacement can)
•
•
•
•
Pour water into the displacement can until it just overflows into a container.
Allow the overflow to run off until there is no more dripping.
Replace the container with an empty measuring cylinder as shown in Fig. 2.
Lower the stone gently into the displacement can and collect all of the displaced
water.
6
Fig. 2
•
•
•
Measure the volume (V1) of the displaced water due to the stone by reading the lower
meniscus. (Remember to read at eye level)
Gently lower the metal bob into the displacement can which contains water and stone
Measure and record the new volume (V2) of the water in the measuring cylinder
Results and calculations
Volume of water (cm3)
Displacement of water
due to stone only (V1)
Displacement of water due
to stone and bob (V2)
Volume of stone = V1
Volume of bob = V2 – V1
Discussion and conclusion
Compare the volume of the bob found by using the direct method ( using the vernier ) and its
volume using the displacement of water method.
Observe and explain the possible measurement errors.
7
Questions
1. What did you observe when the objects were placed in the water?
Why did this occur?
2. Will the results be different if alcohol is used as a liquid instead of water.
3. Suggest why the direct method was not used to determine the volume of the irregular
object.
( Provide brief explanation.)
New Technology – what is happening now
Use of laser to measure distances
( Demonstrate the use of new technologies)
8
VIDEO 2
MAIN TOPIC:
Statics
SUB TOPICS AND THEORY TO COVER:
Centre of gravity
Stability and Equilibrium
Oscillations and Period of a pendulum
Experiments:
Centre of gravity of an irregular object
Period of a pendulum
Every day Application – where does it apply
The design of racecars is done in such a way that they have a low centre of gravity. This makes
them more stable when they are turning corners as they are likely to flip over at high speeds.
Sample Theory
The centre of gravity of an object represents the position where all the weight of the object seems
to act. The object will balance at its center of gravity.
The period (T) of a simple pendulum is governed by the equation T = 2π√l/g. By analyzing the
equation, it shows that the period is affected by l and g, where l is the length of the pendulum and
g is the gravitational field strength. On earth g is constant.
Laboratory Expt.
Centre of gravity of an irregular lamina.
Determine the factors affecting the period of a simple pendulum.
Apparatus:
Irregular lamina (thin cardboard / aluminum sheet)
Retort stand, boss and clamp
Plumb line
Pencil
Cork
Pin
EXPERIMENT (a) - Centre of gravity of an irregular lamina
9
Objective:
•
•
•
•
•
•
•
•
To determine the centre of gravity of an irregular lamina
Set up the retort stand clamp and boss
Attach the cork to the clamp
Bore a hole at the edge of the lamina with a pin
Place the pin through the cork (with the lamina still attached)
Ensure the lamina is able to swing freely.
When the plumb line has settled mark a dot on the lamina where the plumb line ends.
Use your pencil and rule to draw a straight line from the pin-hole to the dot.
Repeat the procedure twice putting holes at other points along the edge. See Fig. 2.1
Diagram
Fig. 2.1
Observation
What is the most observable thing about the lines drawn?
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Discussion and Conclusion
Questions and Explanations
EXPERIMENT (b) – Simple Pendulum
Objective: To determine the factors affecting the period of a simple pendulum
Apparatus:
Retort stand, boss and clamp
String
Bobs of different masses
Cork or two pieces of wood
Pin
Ruler
Marker
Triple beam balance
Procedure
•
•
•
•
•
•
•
•
•
•
•
•
Measure and record the mass of each bob
Set up the retort stand clamp and boss
Attach the cork to the clamp
Place the pin in the cork / or place the string through the two blocks of wood
Make the pendulum by attaching the smaller bob to the string
Measure 5 cm from the centre of the bob to the string
Mark this position
Continue making marks 5cm from this point until there is a total of 7 marks.
Hang the pendulum from the last marked position.
Record the time for twenty oscillations (Remember to stand to the side and use the
countdown method) Repeat this.
Repeat the procedure until there are two sets of times for each mark.
Repeat the experiment using the larger bob.
11
Observation
Results and Calculations
a. Small Bob
Mass =
g
Length/m
Time for
twenty
oscillations
t1/s
Time for
twenty
oscillations
t2/s
Average Time
for twenty
oscillations
t/s
Period
T= t/20
T/s
0.35
0.30
0.25
0.20
0.15
0.10
0.05
12
b. Large Bob
Mass =
g
Length/m
Time for
twenty
oscillations
t1/s
Time for
twenty
oscillations
t2/s
Average Time
for twenty
oscillations
t/s
Period
T= t/20
T/s
0.35
0.30
0.25
0.20
0.15
0.10
0.05
Discussion and Conclusion
Questions and Explanations
1.
Did the period of the pendulum change when?
a. The length of the pendulum was changed. If so how did it change?
b. The large bob was substituted by the small the bob. If so how?
c. Therefore which factor affected the period of the pendulum.
Innovation - challenge the students and give some ideas
Let some of the sand leak out and discuss how the period is affected
New Technology – what is happening now
Atomic Clock
13
VIDEO 3
MAIN TOPIC: Moments
SUB TOPICS AND THEORY TO COVER:
Principle of moments
Equilibrium and parallel forces
Experiment: Determine the mass of a uniform lever
Every day Application – where does it apply
See- saw, gate-booms
SampleTheory
The moment of a force is the product of Force and the distance between the force and the pivot.
The Principle of moments states that for balancing total anticlockwise moment is equal to the
total anti clockwise moment.
Laboratory Expt.
Determine the mass of a uniform lever using the principle of
moments
Objective:
To determine the mass of a uniform lever using the principle of moments.
Apparatus:
Uniform lever such as a meter rule
Retort stand, clam and boss
String
50g mass
100g mass
14
Procedure
•
Set up the retort stand clamp and boss.
•
Use the string to make a loop around the ruler as shown in the diagram
•
Suspend the ruler so that it balances. This represents the centre of gravity of the ruler.
Record this position
•
Shift the position of the loop so the ruler is now unbalanced. Note this position, it
represents the pivot.
•
Make a similar loop around the 50g mass and loop it around the ruler. Ensure the
string lies straight across the rule so that the numbers are aligned.
•
Adjust its position until the ruler is once again balanced. Note this position
•
Repeat the procedure using the 100g mass
Diagram
Observation
Results and calculations
1. 50g Mass
Position/cm
Centre of gravity
Position of pivot
Position of 50g mass
Distance from pivot/cm
(d1)
(d2)
By applying the principle moments calculate the mass of the ruler
Total anticlockwise moment = Total clockwise moment
Weight of ruler x d1
= Weight of 50g mass x d2
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2. 100g Mass
Position/cm
Centre of gravity
Position of pivot
Position of 100g mass
Distance from pivot/cm
(d3)
(d4)
By applying the principle moments calculate the mass of the ruler
Total anticlockwise moment = Total clockwise moment
Weight of ruler x d3
= Weigh of 100g mass x d4
Average weight of ruler =
Mass of ruler = Average Weight / Gravitational field strength (g)
Discussion and Conclusion
Questions and Explanations
Determine the mass of the rule using your triple beam balance and compare this result with that
obtained using moments.
Innovation - challenge the students and give some ideas
1. Find the mass of a non-uniform lever such as the gate boom
2. A boom that was badly built refuses to stay down. Suggest two way the manufacturer can
correct this flaw.
New Technology – what is happening now
Trains with the tilting cars
VIDEO 4
MAIN TOPIC: PRESSURE
16
SUB TOPICS AND THEORY TO COVER:
Force and Pressure
Pressure in liquids and gases
Atmospheric pressure
Experiment: Pressure exerted by an irregular object
Every day Application – where does it apply
Hot air balloon, boundary yellow lines at train stations, low pressure centre at the eye of a
hurricane, pilot pressurizing and depressurizing an airplane. Applications of liquid (hydraulic)
pressure.
Pressure is the force acting normally per unit area. As the area increases the pressure decreases.
Laboratory Experiment
Determine the pressure exerted by an irregular object.
Objective: To determine pressure exerted by an irregular based object
Apparatus:
Graph paper
Flat shoe
Triple beam balance
Procedure
•
Outline the base of the shoe on the graph paper
•
Determine the approximate area of the base by counting the number of cm squares.
•
Convert this area in cm2 to m2
•
Measure the mass of the object using the triple beam balance.
•
Convert the mass in g to kg
•
Calculate the weight of the object.
17
Diagram
Results and Calculations
Area/cm
Area/m
Mass/g
Mass/kg
Weight/N
Pressure/Nm
Observation
Discussion and Conclusion
Questions and Explanations
1.
Would the pressure remain the same if the object was inverted? Explain your answer
Innovation - challenge the students and give some ideas
Egg and bottle experiment, pressure due to a column of liquid, Bed of nails.
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New Technology – what is happening now
Flight
VIDEO 5
MAIN TOPIC: Momentum
SUB TOPIC AND THEORY TO COVER:
Momentum and Newton’s second law of motion
Momentum and Impulse
Conservation of Momentum and collusions
Experiment: Trolley’s collision to study the principle of momentum
Every day Application – where does it apply
Car crashes
Game of pool, space applications
Laboratory Experiment
Using the trolleys to measure speed and apply the principle of
momentum
Objective
To measure the speed of a trolley by applying the principle of moments
B
A
19
Apparatus:
Ticker tape
Trolleys
Procedure
•
•
•
•
•
•
•
Set up the ticker tape as shown in the diagram.
Set the Trolley A in motion and allow it to collide with Trolley B
The ticker tape will record the motion
Cut the tape in two where each section represents the motion before and after the
collision
Use the tape to measure the speed of Trolley A before the collision and Trolleys A
and B after they have collided.
This is done by cutting the strip at each dot and placing them side by side on graph
paper as shown in the diagram. This is actually a distance time graph of the motion
Calculate the gradient of the both graphs. This represents the speed of the motion.
Diagram
Results and Calculations
20
Graph
Gradient of graph 1
m = change in y axis
change in x axis
Gradient of graph 2
m = change in y axis
change in x axis
Observation
What happen after they collided.
Discussion and Conclusion
Questions and Explanations
1.
What type of collision is represented here
2.
Was momentum conserved
3.
Was kinetic energy conserved?
4.
If the trolleys rebounded rather than remaining together, what type of collision would
this represent. Would any of the above be conserved.
Innovation - challenge the students and give some ideas
Put a fan on the trolley
New Technology – what is happening now
Rockets
21
VIDEO 6
MAIN TOPIC: HEAT TRANSFER
SUB TOPICS AND THEORY TO COVER:
Heat Transfer – Conduction, Convention, radiant heat
Heat Capacity and Specific Heat
Experiment: To measure the specific heat capacity of a liquid
Every day Application – where does it apply
Radiator
Land vs Sea Temperature, Heat sinks in computers, gas compression in refrigerators
Laboratory Experiment
Describe activities to determine by electrical method or method of
mixtures the specific heat capacity (S.H.C.) of metals and liquids.
If a liquid of known mass m1, known specific heat capacity c1, at kelvin Temperature T1, is
mixed with another liquid of known mass m2, and unknown specific heat capacity c, at
kelvin Temperature T2, (assuming T1 > T2), and this is then in a near perfectly sealed thermal
enclosure so that energy loss is negligible, then the mixture will reach final
temperature T, (with T1 > T > T2), such that:
energy lost by the first liquid = energy gained by second liquid of unknown S.H.C.
and thus: m1 x c1 x (T1 – T) = m2 x c x (T – T2), so the value of c can then be found.
Laboratory Expt. – Standard Lab expt.
Comparing SHC of water vs coolant using method of mixtures
Apparatus
samples of water and coolant
digital balance
beakers/conical flasks
well-lagged thermal enclosure
thermometers
heat source
Procedure
1. Measure the mass of each of the two beakers to be used.
2. Pour a sample of water in one beaker and measure the mass of the
beaker.
3. Record the mass of water (e.g. 0.250 kg).
4. Pour a sample of coolant of similar volume to the water, in the other
beaker and measure its mass.
5. Record the mass of coolant (e.g. 0.345 kg) and its temperature (T2).
22
6. Use the heat source to heat the beaker with water for about 2 minutes,
while recording its temperature to the maximum value (T1).
7. Quickly pour the coolant into the water, place the beaker in the
enclosure, and record the final steady state temperature, T.
thermometer
before
coolant of known temp. and mass
water of known mass and temp.
after
mixture of coolant and water of known mass
Observation
Number
#1
#2
Substance
Water
Coolant
Mixture
Water
Coolant
Mixture
Mass in
Temperature in oC or K
kilogrammes Initial Temp Final Iemperature
m1
T1
T2 (T1 > T2)
m2
T2
T2 (room temp.)
m3
T2
T3 (T2 < T3 < T1)
m4
T4
T4 (T4 > T5)
m5
T5
T5 (room temp.)
m6
T5
T6 (T5 < T6 < T4)
Precautions
1.
Ensure initial and final temperature readings are STEADY STATE values
2.
Transfer mixture to insulated area as quickly as possible
3.
Read mass values as accurately as possible
4.
Read temperature values as accurately as possible
Results and calculations Ensure that all values are expressed in S.I. units.
Find the S.H.C. of the coolant by using the relationship:
S.H.C. for coolant, c
=
mass of water x S.H.C. of water x (T1 – T)
mass of coolant x (T – T2)
23
Innovation - challenge the students and give some ideas
Alternative Cooling Method for vehicle engines by increasing air flow.
Using different material to build the engine.
Directing the flow of heat.
New Technology – what is happening now
Fire retarding fabrics
VIDEO 7
MAIN TOPIC: Waves
SUB TOPICS AND THEORY TO COVER:
Transverse and longitudinal waves
Wave properties. Wave equation, Frequency, Wavelength
Experiments: Use of ripple tank to study wave properties
Everyday Application
Waves on the sea
Ultra sound
Cell Phones
Microwaves
Loud speakers
Theory
Objective D1.4: Extract information about wave parameters from graph representing waves
Objective D1.2: Recall the meaning of speed, frequency, wavelength, period, amplitude,
phase and solve problems involving these
The concept of the spectrum to include radio and ultra violet
Laboratory exercise
Use ripple tank to identify the properties – Period, wavelength,
speed, frequency.
Apparatus
ripple tank
wave source
timer e.g. stop watch
metre rule or other suitable length measuring device
24
Procedure
1. Activate the wave source and observe the transverse water waves in the
ripple tank.
2. Count and use the timer to find the number of waves generated per
second [frequency].
3. Use the metre rule to measure the distance between adjacent crests
or troughs [wavelength].
4. Use the timer and metre rule to find the time taken for one of the
waves to move a specific distance [speed].
Precautions
1.
Ensure wave spacing is CONSTANT for measurements
2.
Take timing for positions between wave source and end of the ripple tank
3.
Ensure that the reflected waves do not interfere with measurements
4.
Adjust the wave source frequency to ensure ease of taking readings
Results and calculations Ensure that all values are expressed in S.I. units.
Find the frequency of the waves - # of waves per second, and then the period of the wave
as the multiplicative inverse/reciprocal of the frequency.
Find the speed of the wave from the relationship: speed = distance/time
Wave properties
Number of waves per
second (frequency)
Distance between adjacent
crests/troughs (wavelength)
Time for ONE wave to
travel distance, d
(speed = distance/time)
1st value
2nd value
3rd value
Mean value
Top
vie
w
of
ripp
le
tank
for
speed measurements
wave X
source
wave
motion
wavelength
Demonstrate the wave effect – reflection, refraction and diffraction
and identify the properties of the wave that changes.
Apparatus
Ripple tank
Wave source
Barriers of different shapes – plane and curved
25
Procedure
1. Activate the wave source and observe the transverse water waves
generated, looking at frequency, wavelength and speed.
2. Position one of the plane barriers and observe the incident and reflected
waves, noting differences and similarities.
3. Position one of the curved barriers and observe the incident and
reflected waves, noting similarities and differences.
4. Place material in the ripple tank orientation to the water at two different
depths, e.g. from deeper to shallower, and observe the incident wave and
refracted waves as they move from the deeper to shallower water, noting
similarities and differences.
5. Position two (2) of the plane barriers to form a small gap and observe
the wave(s) as the come to [incident wave] and go from [diffracted wave]
the gap, noting similarities and differences.
Top view of ripple tank for wave reflection
wave source
X
wave source
incident waves
X
incident waves
plane
barrier
reflected waves
curved
barrier
reflected waves
Results and calculations
Name the similarities and differences, if any, found for wave frequency, wavelength and
speed in the case of: (i) incident and reflected waves – frequency/speed/wavelength
same but direction of travel is reversed
(ii) incident and refracted waves (for water of different depths] –
frequency same but wavelength/speed changes
(iii) incident and diffracted waves – wavelength same but speed/
frequency changes
Side view of ripple tank for wave refraction
wave source
26
Top view for wave refraction
wave X
source
Top view for wave refraction
wave X
source
Find the speed of the wave using two method and compare answers
Results and calculations Ensure that all values are expressed in S.I. units
From the values of frequency, wavelength and speed done in the first procedure with the
ripple tank, compare the value obtained for wave speed using the relationship:
speed = distance/time
with the value obtained using the relationship:
speed = frequency x wavelength
Wave properties
Number of waves per
second (frequency)
Distance between adjacent
crests/troughs (wavelength)
Time for ONE wave to
travel distance, d
(speed = distance/time)
1st value
2nd value
3rd value
Mean value
Inn
ova
tion
Dis
play
sou
nd
wav
27
es in some visible format e.g. light powder in enclosed tube with speaker at one end
New Technology
Ultrasonic Toothbrushes for whitening teeth and cleaning jewelery
VIDEO 8
MAIN TOPIC:
Action of Lenses
SUB TOPICS AND THEORYTO COVER:
Reflection and refraction of light
Converging and diverging properties of lenses
Focal length, magnification, and power of lenses
Experiment: Focal length of convex and concave lenses
Everyday Application
Magnifying glasses
Spectacles etc.
Sample Theory
Draw ray diagrams to show how a single lens is used as a – magnifying
glass/simple lens camera/projector
What is a lens? – change light directions from object to forms images which may be real
(can be focused on a screen) or virtual
: Illustrate the effect of converging and diverging lenses on a beam of
parallel light.
Convex and concave lenses – Convex lenses are thicker at the centre than the edges and produce
real or virtual images from a real object, depending on the object distance from the lens, while
concave lenses are thicker at the edges than the centre and ALWAYS produce virtual images for
a real object
Laboratory exercise
Determine the focal length of a converging lens.
Apparatus
[thin] converging lens
lens holder
light beam and screen or optical pins
suitable surface
paper sheets
meter rule
Procedure
1. Place lens in holder and position at centre of paper sheet placed
28
on surface
2. Focus narrow beam of light near the centre of the lens
3. Place screen on other side of lens and move until pinpoint of light is
seen. Note that you may have to shift the light source slightly towards or
away from the screen to get the sharp focus.
4. Measure the distances from – light source to lens (object distance, u)
and image/pinpoint position to lens (image distance, v)
Results and calculations
Find the focal length, f, of the lens by using the relationship:
1/u
+
1/v
=
1/f
Diagram of two or more light rays from source passing
through lens and converging at image position
To investigate the nature, position and size of an image formed by a
converging lens.
Apparatus
[thin] converging lens of known focal length
lens holder
optical pins or light beam
screen
suitable surface
paper sheets
Procedure
1. Place lens in holder and position at centre of paper sheet placed on surface.
2. Mark of distances of focal length (f) and twice the focal length (2f) on
either side of the lens.
3. Position one pin at distance greater than 2f on one side of the lens.
4. Move the screen on the other side of lens and note position for sharpest
image of object pin, as well as image size and orientation in comparison to
object size and orientation.
5. Repeat steps 3 and 4 for the object pin at distance 2f, as well as
between 2f and f.
Side view of experimental setup for convex lens
object
F
u
convex lens
v
F
screen
image on
screen
29
6. Position the object pin at distance f and try to obtain the image by
moving the screen on the other side of the lens, then look through the
same side of the lens as the screen for the image, and place a second pin at
its apparent position, which should be on the same side of the lens as the
object.
7. Note the position of the image pin, as well as the size and orientation of
the image as seen through the lens, in comparison to the object size and
orientation.
8. Place the object pin at various distances between f and the lens and find
the image position in each case, following procedures 6 and 7, as well as
image size and orientation in relation to the object, in each case
Side view of experimental setup for concave lens
image
object
concave lens
F
F
eye
Results and calculations
Record your findings for converging lens of focal length f, in a table similar to the one following:
Object position, u
u > 2f
u = 2f
f < u < 2f
u=f
u<f
Image position, v
Image size
Image orientation
Innovation
Use of lens combinations – two converging lenses/two diverging lenses/converging with
diverging lens
New Technology
Use of prisms instead of lenses
30
Using lasers for light beam and lenses to give display patterns for advertising etc.
VIDEO 9
MAIN TOPIC: Electromagnetism
SUB TOPICS AND THEORY TO COVER:
Magnetic effects of electric current
Electromagnets
Electromagnetic induction
Experiment: Magnetic force due to current flowing through a conductor
Everyday Applications:
Electromagnets find very important uses in our everyday lives. The electric bell, the magnetic
relay used in car starter motors, circuit breakers, telephone earpiece and electronic locks are
some of the popular uses . Use in energy applications.
When current passes through a conductor, magnetic field will be generated around the conductor
and the conductor become a magnet. This phenomenon is called electromagnetism. Since the
magnet is produced by electric current, it is called the electromagnet.
When current flows through a conductor, magnetic field will be generated. When the current
ceases, the magnetic field disappear
When a current-carrying conductor is placed in a magnetic field, the interaction between the two
magnetic fields will produce a force on the conductor.
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The direction of the force can be determined by Fleming's left hand rule as shown in Figure
below.
The strength of the force can be increased by (a) increasing the current (b) using a stronger
magnet.
Theory to be included according to the sub topics of the videos.
Laboratory Experiment
MAGNETIC FORCE DUE TO CURRENT FLOWING THROUGH A CONDUCTOR
Procedure:
Set the balance to read zero grams. Set the power supply to 3.0 amps and note the movement of
the conductor. Does the balance read positive or negative mass?
Adjust the position of the conductor so that it is centered in the gap as indicated by
the pointer, and read the effective mass as indicated by the balance, and multiply this number by
the acceleration of gravity.
This is the magnetic force due to the current of 3.0 amps passing through the conductor in the
magnetic field.
Take several readings of this force for different currents. Be sure to tare the balance for zero
current each time and then take a reading with the current turned on.
Make a plot of the force verses the current.
Comment on the relationship between the force and the current.
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Innovation
Electromagnetic pulse is used to treat cancer and brain disorders. A pulse is sent through the
skull. Low frequency pulse will inhibit brain activity while high frequency pulses will excite
brain activity.
New Technology
Eelectromagnets have been designed to create very strong magnetic fields. The design takes the
form of a quadrupole used for high power proton acceleration
VIDEO 10
MAIN TOPIC: ELECTRONICS
SUB TOPICS AND THEORY TO COVER:
Properties of Semiconductor diode and Light Emitting Diodes
Half and full wave rectifications using diodes
Logic Gates and truth tables
Analysis of circuits using up to three logic gates
Applications of logic gates in sensor circuits
Everyday Applications:
Power supply circuits, computers, Cell phones, light, temperature sensor
circuits
Experiment1: Connect and test a light sensor circuit.
Experiment 2: Connect and test logic gates equivalent electronic
circuits performing the functions of AND and NAND gates.
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Essential Content:
Practical Examples/Demonstrations:
Theory and applications
Apparatus/Equipment required
While using electronic circuits, explain the operation of the circuits
Demonstrations
Precautions/Safety Measures in the use of devices
Discussion/Conclusion
Examples of trends in Technology/New Technologies and
Innovations
Nano Technologies, small size and more features of devices
Summary of important concepts
Assessment of skills learnt
( Short Quiz, interactive questions/answers)
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