Questions not addressed during lessons

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Electricity 1: Design and explanation of initial circuits for Quiz Show

SST National Day Celebration includes a quiz show “We are Singaporean”. You are tasked to create a simple light system for 3 teams of participants. The light system will allow the host to identify the first team that choose to answer the question. You have the following items to build you circuit, batteries, wires, switches and identical light bulbs.

Create a new post for your group's initial design of the circuit.

Your post must include:

a) Diagram of your circuit (Take a picture of your drawing)

b) Explanation of your circuit

c) Description of how the current flows in your circuit.


Students' Responses
Group 1 Abigail, Aisyah, Vivek
Group 2 Pranavi, Wu Shen, Kun Yao
Group 3 Catherine, Daniel, Samuel
Group 4 Mohit, Elijah, Mirza
Group 5 Kieren, Matthew, Kenneth
Group 6 Amrit, Zhixiang, Jonathan
Group 7 Adam, Zhi Yong, Alpha

Students' videos on Transverse and Longitudinal Waves

The following are videos of students demonstrating transverse and longitudinal waves.

Kun Yao, Kieran and Amrit
Elijah and Kenneth
Catherine, Alpha and Matthew
Zhi Xiang and Wu Shen - Longitudinal Waves
Zhi Xiang and Wu Shen - Transverse Waves

Refraction

Students' Responses
Adam and Zhi Yong
Elijah and Kieran
Jonathan, and Wu Shen
Abigail, Aisyah, Catherine and Pranavi
Daniel and Zhi Xiang
Amrit and Alpha
Mohit and Mirza
Samuel and Vivek



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Do the following activities in pair or three.


Activity 1 (10 min)
1. Using a rectangular plastic block and ray box, verify what you have learned about refraction.

2. Shine the light ray through the longer side of the rectangular plastic block.

3. Observe the the path of the light ray from the top. and 

4. Record down your observation on how the light ray travels as it moves from air to plastic block and as it moves from plastic block to air.

5. Is there an angle of incidence where the light ray does not refract?

6. Support your answer with images.

Your observation should look like:

We observed that when light ray travels from air to the plastic rectangular block, it ............

When the light ray travels from plastic ..........

It is observed that when the angle of incidence is ........, there is no refraction.

Activity 2 (30 min)
1. Using a semi-circular plastic block and ray box, investigate the path of a light ray as it moves from the plastic block to air

2. Place the semi-circular block in the middle of the A3 size Paper Projector with the straight edge aligned to the horizontal ruler.

3. Shine a light ray through the curved surface of the semi-circular block for angle of incidence between 10 to 50 degrees.

4. Observe the path of light ray as it moves from the semi-circular block to the air.

5. Record your observation with respect to both reflected and refracted rays

6. Is there an angle when there is no longer any refraction?

7. Support your answers with images.

Components of Electromagnetic Spectrum

Read the post of the other groups in the following order.

After reading,

- provide constructive comments/questions to the group

  - content (what information is incorrect/missing?)

  - clarity (is the information clear? is there anything that you do not understand?)

  - presentation (can the information be presented more effectively?)

- read others' comments before posting. Do not repeat the same comment.

- You have 5 minutes for each electromagnetic wave

- We will rotate after every 5 minutes

When you are done, review the comments given and improve on your post.

The links to each of the components are found below.

Gamma Rays
X-rays
Ultraviolet
Visible Light
Infrared
Microwaves
Radio waves

(General Waves Properties) Example 3 - Can speed of wave change?

In pair or three, upload your answer to Example 3. State your names when you upload your answer.

(a) Calculate the speed of the wave pulse.

(b) Is it possible to change the speed of the wave pulse (of the same width)?  Support your answer with evidences such as screenshots of simulation showing different/same time taken of wave pulse generated in different conditions to travel 90.0 cm.


Students' responses
Daniel and Wu Shen
Mirza, Zhi Yong and Jonathan
Elijah and Kieran
Vivek and Kun Yao
Matthew, Mohit and Kenneth
Alpha and Adam
Amrit, Abigail and Zhixiang

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Explanation:

We used the parallel arrangement as we can light up different light bulbs at the same time.
Bulbs that as arranged in parallel are brighter than those in a series arrangement.

Electronic Circuit By Aisyah, Abigail and Vivek

How it works:

The electricity from the dry cell battery flows through the wires to all the three different bulbs through the 3 paths (3 different arrows - black red green)

When two of the bulbs are lit up, the brightness will be the same as it is a parallel circuit.

When three three bulbs light up all of the will be the same but will be dimmer than if it was only 2 bulbs or one bulb light up.

If it is in a series circuit one bulb is dependent on the other however in a parallel circuit it is no dependent which is more suitable for this activity.

1.1 Light for Quiz Show

When a person presses the switch the light will light up before the other people and thus the host will see who lit up the bub first

Daniel,Samuel and Catherine's circuit diagram

Length AB=BC=CD=DE
AB,BC,CD and DE have equal lengths.When X,Y or Z is pressed,you can tell which person presses the switch the first.
(There is no split second human error)

When the pink switch is closed, the current takes the pink path and lights up the bulb on that path.

When the yellow switch is closed, the current takes the path of the yellow line and lights up the bulb on that path.

When the black switch is closed, the current takes the path of the black line and lights up the bulb on that path.

1.1 Task: Light for quiz show - Elijah, Mirza, Mohit

This is a parallel circuit.

Therefore, when the first person presses the button, it will close the circuit which will light up the bulb.

The current flow from the longer (positive +) side of the battery. And the amount of current flowing through each of battery is the same. 

When one bulb lights up after one another, the brightness of each bulb will decrease.

When all the switches are closed, the brightness of each bulb will remain the same.

Adam, Alpha, ZhiYong light system for quiz show

The circuit works because when one switch is closed, only one light bulb lights up. Each switch only activates one light bulb, and does not affect the rest. The first person to close the switch, his/her light bulb will light up first. When all the switches are closed, the light bulbs will be of equal brightness, as the current is equally split.

We can also use different colours for the light bulbs, so that the judge can differentiate who pressed the switch first more easily.

Transverse Wave by zhixiang and wushen

Longitudinal Wave by zhixiang and wushen

Catherine, Alpha and Matthew transverse WAVES :)

Video of Transverse and Longitudinal Waves

Transverse and Longitudinal Waves By Kun Yao, Kieren and Amrit

Samuel n VIVEK TADIKAMALLA

Activity 1

We observed that when light ray travels from air to the plastic rectangular block, it bends towards the normal. This is because the light travels from a less dense medium to a denser medium. When the light ray travels from plastic to air, the light bends to its normal angle which is away from the medium. This is because the light moves from a denser medium to a less dense medium. We also observed that at angle 90 degrees, there is no refraction.


























Activity 2

We observed that there is no longer any refraction when the angle of reflection is 45 degrees.

Mohit and Mirza: Refraction

Activity 1

We observed that when light ray travels from air to the plastic rectangular block, it bends towards the normal. This is because the light travels from a less dense medium to a denser medium. When the light ray travels from plastic to air, the light bends to its normal angle which is away from the medium. This is because the light moves from a denser medium to a less dense medium. We also observed that at angle 90 degrees, there is no refraction.


Activity 2


We observed that the ray of light when at 10 to around 40 degrees, there is a refraction and a very weak reflection of rays

However, at around 43degrees, there was no angle of refraction. This is known as critical angle whereby if the incident angle were to increase and bends away from the normal, there will no longer be a ray of refraction.

There is no angle of incidence for the rectangular block. The laser just travels in a straight path.

For the semi circrcular block with the laser at 10 degrees, The refracted ray bends away from the normal by 6 degrees.

For the semi circrcular block with the laser at 20 degrees, The refracted ray bends away from the normal by 16 degrees.

For the semi circrcular block with the laser at 30, the refracted ray bends away at an angle of 26

For the semi circrcular block with the laser at 40 , the reflected ray bends away from the normal at 36.

For the semi circrcular block with the laser at 50, the reflected ray disappears.

Refraction-Daniel Chan and Zhi Xiang

We observed that when light ray travels from air to the plastic rectangular block, it bends towards the normal.
When the light ray travels from the plastic block to air,the light ray travels away from the normal.
It is observed that when the angle of incidence is 0 degrees, there is no refraction.


There is no longer any refraction when the angle of reflection is 45 degrees.

Refraction - Abigail, Aisyah, Catherine & Pranavi~~

Activity 1

Is there an angle of incidence where the light ray does not refract? Yes. 0 degrees.

We observed that when light ray travels from air to the plastic rectangular block, it reflected

When the light ray travels from plastic block to air, it is observed that when the angle of incidence is 0, there is no refraction.

Activity 2

Is there an angle when there is no longer any refraction? Yes. 42.5 degrees.

Jonathan Then and Khoo Wu Shen: Refraction

Activity 1

We observed that when light ray travels from air to the plastic rectangular block, the refracted ray bends towards the normal.When the light ray travels from plastic rectangular block to the air, the refracted ray bends away from the normal. It is observed that when the angle of incidence is at 0 degrees, there is no refraction.

Image of the rectangular block when the angle of incidence is set at 0 degrees.

Activity 2

We observed that when light ray travels from the plastic semi-circle block to air, the light ray bends away from the normal. This was seen for angle of incidence of 10 to 40 degrees.

When its was 50 degrees, there was no refracted ray. This is known as the Total Internal Reflection. When further tested, the critical angle was 45 degrees. This means that any degree above 45 degrees will be know as Total Internal Reflection.

Refraction - Elijah and Kieren

Activity 1

We observed that when light ray travels from air to the plastic rectangular block, it bends towards the normal.

When the light ray travels from plastic it bends away the normal.

It is observed that when the angle of incidence is 0 there is no refraction.

Activity 2

Angle of incidence 30 degrees.

Angle of incidence 50 degrees.

There is an angle when there is no longer any refraction. The angle is 45° .

Angle of incidence 90 degrees.

Adam and Zhi Yong: Refraction

Activity 1

We observed that when light ray travels from air to the plastic rectangular block, the refracted ray moves towards the normal.

When the light ray travels from plastic to air, the refracted ray moves away from the normal.

It is observed that when the angle of incidence is 0 , there is no refraction.

Activity 2

The angle is 45 degrees when there is no longer any refraction.