Dear all,
If you are interested to join the Singpaore Amazing Flying Machine Competition 2012,
Please look register at the following URL http://tiny.cc/safmc2012.
If you would like to clarify any doubts do look for Mr Tan HT.
Thanks.
Monday, September 26, 2011
Wednesday, August 24, 2011
1.2 Single Bulb Circuit
Table 1 represents the possible arrangements for the bulb to light up, and when it does not light up.
By: Nur Shamemi, Teng Zheng Jie
Tuesday, August 23, 2011
Circuit by Blackarant, Lion and Shakti
When one of the contestants presses the switch, the current can flow through the bulb, lighting it up. The curent would flow around the circuit counterclockwise.
The Circuit - tart, ps, jaime
We chose the parallel circuit as no matter how many bulbs you add in , the brightness of the bulbs would be the same.
1.1 Task for Game show - Jia Sheng, Lincoln, Jasper
We use this circuit as the faster one who hit the button first, the light bulb will light up while the rest will not.Not only that,if the bulb is faulty, it still can be switched in for a new bulb or switch.
1.1 Task by Su En and Carisa
Light for Quiz Show
This is the DC circuit. Once each switch is activated, the electric current is able to flow through and to the bulb which will light the bulb up. It is a parallel circuit. 2 batteries, 3 bulbs and 3 switches used.
Members: Benz and Idris
Worsheet 6 Current Electricity and D.C circuit
This is a parallel circuit. The current will flow from the negative point of the battery to each switch. As the switch is broken, the bulbs will not light up. When one of the switch is closed the bulb will light up.
1.1 Task : Light for quiz show
These two represent possible ways to draw the circuit diagram that can be used.
XD
By : Nur Shamemi and Teng Zheng Jie
Light Circuit for Quiz Show
Diagram of circuit
Explanation of circuit
Explanation of circuit
It is a parallel circuit with 2 batteries. There are 3 bulbs and 3 switches, each switch controlling each bulb (To off and on whichever bulb needed). If one bulb fuses, the other 2 teams will still have light so too bad for the third team :(.. The current flows from the positive terminal to negative terminal.
Done by: Christopher Nah, Hao En and Jurvis.
Monday, August 22, 2011
Level Test for Science on 24 August 2011 (Wednesday)
Topics to be tested:
Reflection
Refraction
Sound (Concepts learn in General Wave Properties is needed.)
Duration: 1h
Test Structure:
MCQ - 10 marks
Short Structure Question - 25 marks
Long Question - 10 marks
Total: 45 marks
Things to bring:
Writing materials including pencil
Calculator
Protractor
Ruler
Reflection
Refraction
Sound (Concepts learn in General Wave Properties is needed.)
Duration: 1h
Test Structure:
MCQ - 10 marks
Short Structure Question - 25 marks
Long Question - 10 marks
Total: 45 marks
Things to bring:
Writing materials including pencil
Calculator
Protractor
Ruler
Thursday, August 4, 2011
Frustrated Total Internal Reflection
Under "ordinary conditions" it is true that the creation of an evanescent wave does not affect the conservation of energy, i.e. the evanescent wave transmits zero net energy. However, if a third medium with a higher refractive index than the low-index second medium is placed within less than several wavelengths distance from the interface between the first medium and the second medium, the evanescent wave will be different from the one under "ordinary conditions" and it will pass energy across the second into the third medium. (See evanescent wave coupling.) This process is called "frustrated" total internal reflection (FTIR) and is very similar to quantum tunneling. The quantum tunneling model is mathematically analogous if one thinks of the electromagnetic field as being the wave function of the photon. The low index medium can be thought of as a potential barrier through which photons can tunnel.
The transmission coefficient for FTIR is highly sensitive to the spacing between the high index media (the function is approximately exponential until the gap is almost closed), so this effect has often been used to modulate optical transmission and reflection with a large dynamic range. An example application of this principle is the multi-touch sensing technology for displays as developed at the New York University’s Media Research Lab.
Applications
- Optical fibers, which are used in endoscopes and telecommunications.
- Rain sensors to control automatic windscreen/windshield wipers.
- Another interesting application of total internal reflection is the spatial filtering of light.[2]
- Prismatic binoculars use the principle of total internal reflections to get a very clear image
- Some multi-touch screens use frustrated total internal reflection in combination with a camera and appropriate software to pick up multiple targets.
- Gonioscopy to view the anatomical angle formed between the eye's cornea and iris.
- Gait analysis instrument, CatWalk,[3] uses frustrated total internal reflection in combination with a high speed camera to capture and analyze footprints of laboratory rodents.
- Fingerprinting devices, which use frustrated total internal reflection in order to record an image of a person's fingerprint without the use of ink.
- Flashlights lenses.[4]
Source: Wikipedia
[edit]
Application and uses of Total Internal Reflection
1. Optical Fibers
An optical fiber is a flexible, transparent fiber made of very pure glass (silica) not much wider than a human hair that acts as a waveguide, or "light pipe", to transmit light between the two ends of the fiber. The field of applied science and engineering concerned with the design and application of optical fibers is known as fiber optics. Optical fibers are widely used in fiber-optic communications, which permits transmission over longer distances and at higher bandwidths (data rates) than other forms of communication. Fibers are used instead of metal wires because signals travel along them with less loss and are also immune to electromagnetic interference. Fibers are also used for illumination, and are wrapped in bundles so they can be used to carry images, thus allowing viewing in tight spaces. Specially designed fibers are used for a variety of other applications, including sensors and fiber lasers.
This technology allows more data to be transferred faster and over a period of longer time as compared to normal internet cables. However, such technology is very expensive, if not I would've been able to have a smoother gameplay.
Group members: Christopher Nah, Hao En
An optical fiber is a flexible, transparent fiber made of very pure glass (silica) not much wider than a human hair that acts as a waveguide, or "light pipe", to transmit light between the two ends of the fiber. The field of applied science and engineering concerned with the design and application of optical fibers is known as fiber optics. Optical fibers are widely used in fiber-optic communications, which permits transmission over longer distances and at higher bandwidths (data rates) than other forms of communication. Fibers are used instead of metal wires because signals travel along them with less loss and are also immune to electromagnetic interference. Fibers are also used for illumination, and are wrapped in bundles so they can be used to carry images, thus allowing viewing in tight spaces. Specially designed fibers are used for a variety of other applications, including sensors and fiber lasers.
Group members: Christopher Nah, Hao En
Application/ Uses of total internal reflection ( Lincoln )
Total internal reflection occurs when:
1. A ray of light is incident upon a boundary with an optically rarer medium (one that makes it speed up)
2. The angle of incidence is greater than the critical angle.
The uses and application of Total Internal Reflection :
1. Telecommunications ; Optical fibres
2. Prismatic Optical Instruments
3. Bicycle Reflector
4. Finger printing devices
5. Rain sensors
1. A ray of light is incident upon a boundary with an optically rarer medium (one that makes it speed up)
2. The angle of incidence is greater than the critical angle.
The uses and application of Total Internal Reflection :
1. Telecommunications ; Optical fibres
2. Prismatic Optical Instruments
3. Bicycle Reflector
4. Finger printing devices
5. Rain sensors
Wednesday, August 3, 2011
Application and Uses of Total Internal Reflection
Application of Total Internal Reflection:
1. Optical fibers
- Commonly used in endoscopes and telecommunications
2. Rain sensors or switches in vehicles
- Mainly used to activate a water conservation device connected to an automatic irrigation system that causes the system to shut down in the event of rainfall or to protect the interior of an automobile from rain and to support the automatic mode windshields or wind screens
3. Prism binoculars
- Use the principle of total internal reflection to get an improved image and higher magnification
4. Sparkling diamonds
- Use of the critical angle to cut the diamond which gives its maximum sparkle
5. Gonioscopy
-Used to view the anatomical angle formed between the eye's cornea and iris.
6. Flashlight lenses
-Reflect light through a more optically dense medium to a less optically dense medium.
1. Optical fibers
- Commonly used in endoscopes and telecommunications
2. Rain sensors or switches in vehicles
- Mainly used to activate a water conservation device connected to an automatic irrigation system that causes the system to shut down in the event of rainfall or to protect the interior of an automobile from rain and to support the automatic mode windshields or wind screens
3. Prism binoculars
- Use the principle of total internal reflection to get an improved image and higher magnification
4. Sparkling diamonds
- Use of the critical angle to cut the diamond which gives its maximum sparkle
5. Gonioscopy
-Used to view the anatomical angle formed between the eye's cornea and iris.
6. Flashlight lenses
-Reflect light through a more optically dense medium to a less optically dense medium.
Uses of Total Internal Reflection
In groups of 2 to 3, research on
a) the application of total internal reflection
b) the advantages of using total internal reflection
c) how total internal reflection is used.
Post your findings on the Science Blog.
One post for each application.
Format of Posting
Title: Application/ Uses of total internal reflection
Body:
Illustrate how total internal is used.
The underlying theory
Conclusion:
Advantages compared to other similar device using different technology
Disadvantages (if any)
Name of members
a) the application of total internal reflection
b) the advantages of using total internal reflection
c) how total internal reflection is used.
Post your findings on the Science Blog.
One post for each application.
Format of Posting
Title: Application/ Uses of total internal reflection
Body:
Illustrate how total internal is used.
The underlying theory
Conclusion:
Advantages compared to other similar device using different technology
Disadvantages (if any)
Name of members
Common Misconceptions on Critical Angle and Main Take away for the Day
Please answer the question below in the comment box.
1) How would critical angle of a rectangle glass block change when we
a) increase the thickness of the glass block;
b) increase the angle of incidence of the ray exiting the glass block;
c) change the material of the rectangle glass block to another of higher refractive index?
2) What are the main concept(s) learnt for today's lesson? Give at least 3 of them.
1) How would critical angle of a rectangle glass block change when we
a) increase the thickness of the glass block;
b) increase the angle of incidence of the ray exiting the glass block;
c) change the material of the rectangle glass block to another of higher refractive index?
2) What are the main concept(s) learnt for today's lesson? Give at least 3 of them.
Friday, July 22, 2011
Level Test for Science on 28 July 2011 (Thursday)
Topics to be tested:
General wave properties
Electromagnetic Spectrum
Reflection
Duration: 1h
Test Structure:
MCQ - 10 marks
Short Structure Question - 25 marks
Long Question - 10 marks
Total: 45 marks
Things to bring:
Writing materials including pencil
Calculator
Protractor
Ruler
General wave properties
Electromagnetic Spectrum
Reflection
Duration: 1h
Test Structure:
MCQ - 10 marks
Short Structure Question - 25 marks
Long Question - 10 marks
Total: 45 marks
Things to bring:
Writing materials including pencil
Calculator
Protractor
Ruler
Wednesday, July 6, 2011
Visible Light-Priyanka, Jaime, Shamemi
Waves with a length of between 0.4 and 0.7 micrometers can be detected by the human eye. For these reason we call these waves visible light. As you look around the room everything you see has these waves bouncing off of them.
Looking directly at the sun for even brief periods of time may cause blindness or severe damage to the eye. Solar retinopathy, damage to the eye’s retina due to solar radiation, and blindness to varying degrees and persistence frequently result from sungazing during a solar eclipse. Although vision loss due to this damage is generally reversible, permanent damage and loss of vision have been reported.
The order of the visible spectrum is Red, Orange, Yellow, Green Blue, Indigo, Violet.
The uses are photoelectric copying machines, laser printers, CD players, camera, microscope, telescope, FAX machines, optical recording media, and optical disc mass-storage systems of exceedingly high bit density.
The dangers of visible light is that there is too much exposure to visible light can cause damage to your retina.
Usages of Visible Light in everyday lives.
-- Watch TV
-- Drive without collisions
-- Read newspaper
-- Watch movies
-- Play video games
-- Distinguish red light from green light when driving in the city
-- Navigate correct routes
-- Enjoy view of moon, stars, and planets
-- Learn when it's raining without going outside
-- Read the GPS screen when driving, between unintelligible verbal instructions
-- Read the gate-numbers at the airport, in order to board the correct airplane
-- See where you're going so you don't bump into things and hurt yourself
Sources :
http://wiki.answers.com/Q/What_are_the_everyday_uses_of_visible_light#ixzz1RHkMCCPe
Electromagnetic Spectrum 101:RADIO WAVES :D:D:D
Radio Waves
Radio waves are used not only in radio broadcasting but in wireless telegraphy, telephone transmission, television, radar, navigation systems and telecommunications. Unlike microwaves, radio waves are able to go over obstacles because of their longer wavelengths. radio waves of longer wave lengths are used for AM radio waves while radio waves of shooter wavelengths are used for TV and FM radio.
Dangers:
Large doses of radio waves causes cancer leukemia and other disorders.
By: Teng Zheng Jie, Darryl Lam Wei Cheng and Lionel Lim Yu Xiang
:D
:D
;D
Radio waves are used not only in radio broadcasting but in wireless telegraphy, telephone transmission, television, radar, navigation systems and telecommunications. Unlike microwaves, radio waves are able to go over obstacles because of their longer wavelengths. radio waves of longer wave lengths are used for AM radio waves while radio waves of shooter wavelengths are used for TV and FM radio.
Dangers:
Large doses of radio waves causes cancer leukemia and other disorders.
By: Teng Zheng Jie, Darryl Lam Wei Cheng and Lionel Lim Yu Xiang
:D
:D
;D
Microooooowave - The Nah Theory
Microwaves
Uses
Heating up and cooking food
Radar (Military purposes)
Harmful effects/ disadvantages
Clicks and buzzing sounds (Thermal expansion in parts of the inner ear)
Dielectric heating induced in bodies
Uses
Heating up and cooking food
Radar (Military purposes)
Harmful effects/ disadvantages
Clicks and buzzing sounds (Thermal expansion in parts of the inner ear)
Dielectric heating induced in bodies
Ultraviolet Rays - Teo Yi LIn, Carisa Chan, Teoh Yun
Ultraviolet light is electromagnetic waves with a wave length shorter than visible light. UV Index is to inform public about the intensity of UV radiation . [1-3 means low exposure; 4-6 means medium; 7-9 means high; and above that is extreme exposures.] However, it differs with the skin color too! People with fairer skins are more affected by UV radiation while people with darker skins gets affected slower.
Positive uses for ultraviolet light:
- Produce Vitamin D
- Suntan
- Sterilizing medical equipment
- Bees use the reflection of ultraviolet lights off of flower petals to guide pollen collecting
- check for currency authenticity
Negative uses for ultraviolet light:
- Skin Cancer
- Sun burn
Positive uses for ultraviolet light:
- Produce Vitamin D
- Suntan
- Sterilizing medical equipment
- Bees use the reflection of ultraviolet lights off of flower petals to guide pollen collecting
- check for currency authenticity
Negative uses for ultraviolet light:
- Skin Cancer
- Sun burn
Gamma Rays
One usage of Gamma Rays : To sterilise surgical instruments.
One danger of Gamma Rays : Make your cells cancerous.
New Things:
One of the rays emitted from the nuclear radiation is Gamma Ray.
Detect brain and heart abnormalities.
One video:
http://www.youtube.com/watch?v=LTRUDeJIZ0w&feature=fvst
One danger of Gamma Rays : Make your cells cancerous.
New Things:
One of the rays emitted from the nuclear radiation is Gamma Ray.
Detect brain and heart abnormalities.
One video:
http://www.youtube.com/watch?v=LTRUDeJIZ0w&feature=fvst
X Rays. What about them ?
The full form of X-Ray is X-Radiation. X-Ray is basically a form of electromagnetic radiation. X-Rays have a shorter wavelength than Ultra-Violet Rays and have a longer wavelength than Gamma Rays. The name X-Radiation was named after Wilhem Conrad after he discovered an unknown type of radiation.
The uses of X Rays are useful in the detection of pathology of the skeletal system as well as for detecting some disease processes in soft tissues The different medical uses are the common x rays, computer tomography, fluoroscopy and radiotherapy.
However, the risk of X-rays are a form of ionizing radiation, hence causing radiation sickness. When normal light hits an atom, it can't change the atom in any significant way. But when an X-ray hits an atom, it can knock electrons off the atom to create an ion, an electrically-charged atom. Free electrons then collide with other atoms to create more ions. An ion's electrical charge can lead to unnatural chemical reactions inside cells. Among other things, the charge can break DNA chains. A cell with a broken strand of DNA will either die or the DNA will develop a mutation. If a lot of cells die, the body can develop various diseases. If the DNA mutates, a cell may become cancerous, and this cancer may spread. If the mutation is in a sperm or an egg cell, it may lead to birth defects. Because of all these risks, doctors use X-rays sparingly today.
Done By : Lincoln Chu Mesina , R. Abilash and Jasper Phang
The uses of X Rays are useful in the detection of pathology of the skeletal system as well as for detecting some disease processes in soft tissues The different medical uses are the common x rays, computer tomography, fluoroscopy and radiotherapy.
However, the risk of X-rays are a form of ionizing radiation, hence causing radiation sickness. When normal light hits an atom, it can't change the atom in any significant way. But when an X-ray hits an atom, it can knock electrons off the atom to create an ion, an electrically-charged atom. Free electrons then collide with other atoms to create more ions. An ion's electrical charge can lead to unnatural chemical reactions inside cells. Among other things, the charge can break DNA chains. A cell with a broken strand of DNA will either die or the DNA will develop a mutation. If a lot of cells die, the body can develop various diseases. If the DNA mutates, a cell may become cancerous, and this cancer may spread. If the mutation is in a sperm or an egg cell, it may lead to birth defects. Because of all these risks, doctors use X-rays sparingly today.
Done By : Lincoln Chu Mesina , R. Abilash and Jasper Phang
EM Wave - Infared
What is Infared?
Infared is an energy radiation with a frequency not visible to human eyes. Infrared light lies between the visible and microwave portions of the electromagnetic spectrum. Infared wavelengths ranges. The longer, far infrared wavelengths are about the size of a pin head and the shorter, near infrared ones are the size of cells, or are microscopic. (NASA Science)
Disadvantages:
Infared can damage human cell tissue.
It needs a direct line of sight between the transmitter and receiver. For example, it doesn't work through walls or doors.
It causes Sunburn.
Advantages (Uses of Infared):
Night vision: Night vision devices operate through a process involving the conversion of ambient light photons into electrons which are then amplified by a chemical and electrical process and then converted back into visible light.
Tracking: Infrared tracking, also known as infrared homing, refers to a passive missile guidance system which uses the emission from a target of electromagnetic radiation in the infrared part of the spectrum to track it. Missiles which use infrared seeking are often referred to as "heat-seekers"
Heating: Infrared radiation can be used as a deliberate heating source. For example it is used in infrared saunas to heat the occupants, and also to remove ice from the wings of aircraft (de-icing).
Communications: IR data transmission is also employed in short-range communication among computer peripherals and personal digital assistants.
Others uses:
Hyperspectral imaging, Thermography, Spectroscopy, Meteorology, Climatology, Astronomy, Art history, Biological systems, Photobiomodulation, Health hazard.
Cheers!
Group members: Benz, Jia Sheng, Karan, Idris
Infared is an energy radiation with a frequency not visible to human eyes. Infrared light lies between the visible and microwave portions of the electromagnetic spectrum. Infared wavelengths ranges. The longer, far infrared wavelengths are about the size of a pin head and the shorter, near infrared ones are the size of cells, or are microscopic. (NASA Science)
Disadvantages:
Infared can damage human cell tissue.
It needs a direct line of sight between the transmitter and receiver. For example, it doesn't work through walls or doors.
It causes Sunburn.
Advantages (Uses of Infared):
Night vision: Night vision devices operate through a process involving the conversion of ambient light photons into electrons which are then amplified by a chemical and electrical process and then converted back into visible light.
Tracking: Infrared tracking, also known as infrared homing, refers to a passive missile guidance system which uses the emission from a target of electromagnetic radiation in the infrared part of the spectrum to track it. Missiles which use infrared seeking are often referred to as "heat-seekers"
Heating: Infrared radiation can be used as a deliberate heating source. For example it is used in infrared saunas to heat the occupants, and also to remove ice from the wings of aircraft (de-icing).
Communications: IR data transmission is also employed in short-range communication among computer peripherals and personal digital assistants.
Others uses:
Hyperspectral imaging, Thermography, Spectroscopy, Meteorology, Climatology, Astronomy, Art history, Biological systems, Photobiomodulation, Health hazard.
Cheers!
Group members: Benz, Jia Sheng, Karan, Idris
Tuesday, July 5, 2011
Worksheet 1 Example 3 - Shamemi
a) Calculate the speed of the wave pulse.
wavelength ÷ period
= 90.0 cm ÷ 1.69 s
= 53.3 cm/s (3 sf )
b) Is it possible to change the speed of the wave pulse (of the same width)?
= 53.3 cm/s (3 sf )
b) Is it possible to change the speed of the wave pulse (of the same width)?
The speed of the wave pulse could not be changed.
Abilash Worksheet 1 example 3
a) Speed = d/t , therefore
= 90cm/1.69s
= 53.3cm/s
b) The effect can be controlled by the
tension of the string.
= 90cm/1.69s
= 53.3cm/s
b) The effect can be controlled by the
tension of the string.
Monday, July 4, 2011
Example 3 - Tay Pei Shan
a)
90 ÷ 1.69 = 53.3 (3 S.F.)
b) It is possible by changing the tension.
Before :
Tension - High
After :
Tension - Medium
Worksheet 1 example 3: Priyanka
a) Calculate the speed of the wave pulse.
ANS: 90.0 cm ÷ 1.69 s
= 53.3 cm/s (3.S.F)
b) Is it possible to change the speed of the wave pulse (of the same width)?
ANS: Yes, it is possible when we change the tension from high to low. The speed differs.
Worksheet 1 - Example 3 -Goh Jia Sheng / Jasper Phang
a)
90cm / 1.69s = 53.3cm/s (3sf)
Velocity of wave pulse is 53.3cm/s
b)
Yes, it is possible to change the speed of the wave pulse (of the same width).The increase in amplitude causes the amplitude of the wave to increase. X
The increase in pulse width causes the pulse width to increase. X
The increase in damping will cause the wave to lose energy and return to rest position. X
The decrease in tension ill cause the speed of the wave to decrease. √
Worksheet 1 Example 3 - Yi Lin
a) speed of wave pulse
= wavelength ÷ period
= 90cm ÷ 1.96s
= 53.3cm/s [3SF]
b) Yes, when we change the tension of the wave pulse
-No change-
-After change-
As wavelength is shorter, speed will change.
= wavelength ÷ period
= 90cm ÷ 1.96s
= 53.3cm/s [3SF]
b) Yes, when we change the tension of the wave pulse
-No change-
-After change-
As wavelength is shorter, speed will change.
Worksheet 1 Example 3 - Yuzhe
a) Speed = Distance/Time
= Wavelength/Period
= 108cm/2s
= 59cm/s
b) Yes, it is possible to change the speed of the wave pulse by increasing or decreasing the tension.
= Wavelength/Period
= 108cm/2s
= 59cm/s
b) Yes, it is possible to change the speed of the wave pulse by increasing or decreasing the tension.
Worksheet 1 Example 3 - Teoh Yun
a) Calculate the speed of the wave pulse.
90÷1.69 = 53.3 (3 s.f.)
Speed: 53.3 cm/s
b) Is it possible to change the speed of the wave pulse (of the same width)?
Yes, it is possible only when the tension is adjusted.
[At first (No changes made)]
[Change in Amplitude (Higher amplitude)]
[Change in Amplitude (Lower amplitude)]
[Change in Tension]
90÷1.69 = 53.3 (3 s.f.)
Speed: 53.3 cm/s
b) Is it possible to change the speed of the wave pulse (of the same width)?
Yes, it is possible only when the tension is adjusted.
[At first (No changes made)]
[Change in Amplitude (Higher amplitude)]
[Change in Amplitude (Lower amplitude)]
[Change in Tension]Koh Su En - Worksheet 1 Example 3
Velocity = wavelength / period
16cm/0.3s = 53.3 cm/s (3 S.F)
(b) Is it possible to change the speed of the wave pulse (of the same width)?
Change in Amplitude:
Result: No change in Velocity
Change in Damping:
Result: No change in Velocity
Change in Tension:
Result: Change in Velocity as wavelength is shorter.
Conclusion: It is possible to change the speed of the wave pulse by changing the tension.
Worksheet 1 Example 3 - Idris
a) Speed = distance/time
= 90cm/1.69s
= 53.3cm/s
b) The speed can be changed by changing the tension of the string.
= 90cm/1.69s
= 53.3cm/s
b) The speed can be changed by changing the tension of the string.
Worksheet 1 Example 3 - Carisa Chan
(a) Calculate the speed of the wave pulse.
Speed = Wavelength/Period
= 90cm/1.69s
= 53.3 cm/s (3 s.f.)
(b) Is it possible to change the speed of the wave pulse (of the same width)?
Control:
Increase in amplitude:
The speed did not change.
Increase in damping:
The speed did not change.
Decrease in tension:
The speed of the wave changed. It became much slower. Therefore, I conclude that it is possible to change the speed of the wave pulse (of the same width) by changing the tension.
Speed = Wavelength/Period
= 90cm/1.69s
= 53.3 cm/s (3 s.f.)
(b) Is it possible to change the speed of the wave pulse (of the same width)?
Control:
Increase in amplitude:
Increase in damping:
Decrease in tension:
Worksheet 1 Example 3 - Lincoln Chu Mesina
Calculate the speed of the wave pulse :
a) Velocity = Wavelength / Period
= 16/0.35
= 45.7cm (3 s.f. )
Is it possible to change the speed of the wave pulse ( of the same width ) ?
The speed of the wave pulse cannot be changed regardless of adjusting the amplitude, the damping and the tension.
Sunday, July 3, 2011
Worksheet 1 Example 3 - Teng Zheng Jie
Amptitude is 6cm, as shown in image 1.1
Image 1.1
Wavelength is 16cm, as shown in image 1.2
Image 1.2
b) I have realised the speed of the wave is only affected by the tension.
90÷1.69 = 53.2544 cm/s
≈ 53.3cm/s
Image 1.1Wavelength is 16cm, as shown in image 1.2
Image 1.2b) I have realised the speed of the wave is only affected by the tension.
90÷1.69 = 53.2544 cm/s
≈ 53.3cm/s
Worksheet 1 Example 3 - Benz Kew
a) Calculate the speed of the wave pulse.
Amplitude (A): 6cm
Wavelength (λ): 16cm
Velocity: λ/T
90/1.69 = 53.2544cm/s
= 53.3cm/s (3 S.F.)
b) It is possible to change the speed of the wave pulse of the same width by adjusting the tension level (From low to high).
Control (Default setup):
Setup where amplitude increases, speed remains the same. (Time and distance as the constant)
Setup where damping increases, speed remains the same. (Energy is lost)
Setup where tension is reduced, speed is slower. (Distance, wavelength and amplitude changes)
Amplitude (A): 6cm
Wavelength (λ): 16cm
Velocity: λ/T
90/1.69 = 53.2544cm/s
= 53.3cm/s (3 S.F.)
b) It is possible to change the speed of the wave pulse of the same width by adjusting the tension level (From low to high).
Control (Default setup):
Setup where amplitude increases, speed remains the same. (Time and distance as the constant)
Setup where damping increases, speed remains the same. (Energy is lost)
Setup where tension is reduced, speed is slower. (Distance, wavelength and amplitude changes)
Saturday, July 2, 2011
Wave Pulse Question (KJ Shakti)
(a) Wavelength = 16cm
Period = 0.35s
Velocity = Wavelength/Period
= 16/0.35
= 45.7 cm/s (3.s.f)
(b) By adjusting the Amplitude, the Pulse Width, the Damping and the Tension, I realized that the speed of the wave pulse could not be changed.
Period = 0.35s
Velocity = Wavelength/Period
= 16/0.35
= 45.7 cm/s (3.s.f)
(b) By adjusting the Amplitude, the Pulse Width, the Damping and the Tension, I realized that the speed of the wave pulse could not be changed.
Worksheet 1: General Properties of Waves - The Nah Theory
Below are our answers for the mentioned worksheet:
1.1 What are waves?
a) What is the source of wave?
Oscillation or vibration. Wave is only created when the rope is vibrated.
b)What is the medium through which the wave moves?
String molecules. The string molecules vibrates as energy is being transferred onto it.
c) Does wave transfer matter?
No. The molecules moves in a up-down oscillating motion, but the wave moves in a left to right horizontal motion. Thus, the wave is not transferring matter as the direction of their motions are different.
d) Does wave transfer energy?
Yes. The energy from one molecule is transferred to another molecule, resulting in similar oscillatory motion and results in a wave.
1.2 Wave terms
Amplitude (Symbol, A, Unit, m) - Maximum displacement from the rest position
Wavelength (Symbol λ, Unit, m) - Distance between any two identical points on successive waves
Period (Symbol T, Unit, s) - Time taken to produce one complete wave
Frequency - Number of complete waves produced per second.
Relationship between Period and Frequency
T = 1/f
f = 1/T
1.3 Graphical Representation of Waves
a) Amplitude of waves is 0.4m
b) Wavelength of wave is 1 and 2/3 m
c) Period of wave is 1.5s
d) Frequency of wave is 2/3s
1.4 Wave speed
Example 2
Speed = Distance/Time
= 1 and 2/3 m / 1.5 s
= 1.11 (3 s.f.)
Example 3
a) Speed = Distance/Time
= 90 cm / 1.69 s = 53 and 43/169 cm/s
b) To change the speed of the wave pulse of the same width, we can either increase the tension of the medium or increase the linear mass density.
Thanks!
1.1 What are waves?
a) What is the source of wave?
Oscillation or vibration. Wave is only created when the rope is vibrated.
b)What is the medium through which the wave moves?
String molecules. The string molecules vibrates as energy is being transferred onto it.
c) Does wave transfer matter?
No. The molecules moves in a up-down oscillating motion, but the wave moves in a left to right horizontal motion. Thus, the wave is not transferring matter as the direction of their motions are different.
d) Does wave transfer energy?
Yes. The energy from one molecule is transferred to another molecule, resulting in similar oscillatory motion and results in a wave.
1.2 Wave terms
Amplitude (Symbol, A, Unit, m) - Maximum displacement from the rest position
Wavelength (Symbol λ, Unit, m) - Distance between any two identical points on successive waves
Period (Symbol T, Unit, s) - Time taken to produce one complete wave
Frequency - Number of complete waves produced per second.
Relationship between Period and Frequency
T = 1/f
f = 1/T
1.3 Graphical Representation of Waves
a) Amplitude of waves is 0.4m
b) Wavelength of wave is 1 and 2/3 m
c) Period of wave is 1.5s
d) Frequency of wave is 2/3s
1.4 Wave speed
Example 2
Speed = Distance/Time
= 1 and 2/3 m / 1.5 s
= 1.11 (3 s.f.)
Example 3
a) Speed = Distance/Time
= 90 cm / 1.69 s = 53 and 43/169 cm/s
b) To change the speed of the wave pulse of the same width, we can either increase the tension of the medium or increase the linear mass density.
Thanks!
Thursday, April 28, 2011
ISS project group and individual report
Dear Students,
I decided not to take the risk of having to deduct your marks for your ISS project therefore I have come up with the following deadlines.
Group Report
Methods and Materials
which include your experimental design and procedures for your experiment.
most part of this is already done in some of the research plan.
DUE: 4th May Wednesday 1200H
Individual Report
Results --DUE: 4th May Wednesday. 1200H
Analysis of results DUE: 4th May Wednesday 1200H
Area of improvement DUE: 3rd May Tuesday 1200H
Area of further studies DUE: 3rd May Tuesday 1200H
Acknowledgment DUE: 3rd May Tuesday 1200H
References DUE: 3rd May Tuesday 1200H
How to submit?
You are to submit to me via e-mail.
Yellow form (remedial form) will be issued for any late submission.
Shabby work will not be entertained and yellow form will be issued.
Which goes to say that you are most likely going to have only 50% of the marks.
So the remedial is good for you to improve.
You have the long weekend to do this. Use your time wisely.
I decided not to take the risk of having to deduct your marks for your ISS project therefore I have come up with the following deadlines.
Group Report
Methods and Materials
which include your experimental design and procedures for your experiment.
most part of this is already done in some of the research plan.
DUE: 4th May Wednesday 1200H
Individual Report
Results --DUE: 4th May Wednesday. 1200H
Analysis of results DUE: 4th May Wednesday 1200H
Area of improvement DUE: 3rd May Tuesday 1200H
Area of further studies DUE: 3rd May Tuesday 1200H
Acknowledgment DUE: 3rd May Tuesday 1200H
References DUE: 3rd May Tuesday 1200H
How to submit?
You are to submit to me via e-mail.
Yellow form (remedial form) will be issued for any late submission.
Shabby work will not be entertained and yellow form will be issued.
Which goes to say that you are most likely going to have only 50% of the marks.
So the remedial is good for you to improve.
You have the long weekend to do this. Use your time wisely.
Thursday, April 21, 2011
ISS Project
Hi all,
Here the repeated announcement for the submission of logbook.
It is due next week 26th April 2011.
In the logbook you should have the following:
1) draft 1 to 2 of the Research Plan.
2) the final draft of the Research Plan.... it can be the 4th or 5th. This should be a clean draft without any of my marking.
This draft will be the draft that i will be making.
** Refer to the rubrics and make sure you have all the requirements.
3) Material list
4) Experimental Design.
Do not paste in the logbook.
I will correct it and you will past it in later.
** Refer to the rubrics and make sure you have all the requirements.
Andy Sim
Here the repeated announcement for the submission of logbook.
It is due next week 26th April 2011.
In the logbook you should have the following:
1) draft 1 to 2 of the Research Plan.
2) the final draft of the Research Plan.... it can be the 4th or 5th. This should be a clean draft without any of my marking.
This draft will be the draft that i will be making.
** Refer to the rubrics and make sure you have all the requirements.
3) Material list
4) Experimental Design.
Do not paste in the logbook.
I will correct it and you will past it in later.
** Refer to the rubrics and make sure you have all the requirements.
Andy Sim
Friday, March 11, 2011
Team assignment for e-Learning
Groups Leader Member Member Member Member
Group 1 Jurvis Tan KJ Shakti R Abilash Teng Zheng Jie Christopher Nah
Group 2 Priyanka Srikanth Jaime Pang Carisa Chan Lionel Lim Syed Ismail Muhammed Idris
Group 3 Nur Shamemi Koh Su En Darryl Lam Teoh Yun Teo Yi Lin
Group 4 Cheng Hao En Lincoln Chu Tay Pei Shan Karan Sarat
Group 5 Jasper Phang Ng Yu Zhe Goh Jia Sheng Benz Kew
Hi all,
Above should be the finalised group of members in your team.
If there is any changes please let me know by this weekend.
Please e-mail if you have any questions at sim_shiang_hann_andy@sst.edu.sg.
Thank you.
Cheers,
Andy
Group 1 Jurvis Tan KJ Shakti R Abilash Teng Zheng Jie Christopher Nah
Group 2 Priyanka Srikanth Jaime Pang Carisa Chan Lionel Lim Syed Ismail Muhammed Idris
Group 3 Nur Shamemi Koh Su En Darryl Lam Teoh Yun Teo Yi Lin
Group 4 Cheng Hao En Lincoln Chu Tay Pei Shan Karan Sarat
Group 5 Jasper Phang Ng Yu Zhe Goh Jia Sheng Benz Kew
Hi all,
Above should be the finalised group of members in your team.
If there is any changes please let me know by this weekend.
Please e-mail if you have any questions at sim_shiang_hann_andy@sst.edu.sg.
Thank you.
Cheers,
Andy
Wednesday, March 9, 2011
e-Learning Week instruction
Hi 2-02,
Please e-mail me a consolidate goggle spreadsheet with
1) the number of teams and team members.
2) the theme that you have chosen
(By the end of the week)
As for the writing assignment
Minimum word: 500
Maximum words: 1000 (no more than 1 page with single spacing)
Please ensure that you cite your reference with APA style.
Thank you.
Andy Sim
Please e-mail me a consolidate goggle spreadsheet with
1) the number of teams and team members.
2) the theme that you have chosen
(By the end of the week)
As for the writing assignment
Minimum word: 500
Maximum words: 1000 (no more than 1 page with single spacing)
Please ensure that you cite your reference with APA style.
Thank you.
Andy Sim
Tuesday, February 15, 2011
Monday, January 17, 2011
Arthropods - Crustacea (Crustaceans)
A crustacea has:
- An entire body divided into 3 parts; the head*, abdomen and thorax**.
- A hard exoskeleton.
- 2 pairs of antennae.
- The thorax bears legs, which may be specified as "walking legs"*** and "feeding legs"****.
Life cycle
- Produce Eggs
- 3 or 4 stages, depending of the animal
If you want to sound smarter, here are the more complicated words but have the same meanings.
*Cephalon
**Pleon
***Pereiopods
****Maxilipeds
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