Introduction on ME

Ohgosh, i have been posting science stuff until that i forgotten to introduce myself

I am Soh Kai Jie from Hwa Chong Institution, Class 1P4, index number 22
My science teacher is Mr Sim Mong Chea, if u have been checking on my blog.
And i am doing this blog for my Science assignment, Hwa Chong aims to produce their students as all-rounded students, so in terms of presenting skills and oral skills and other skills too.
So this is the assignment assign by teachers to kind of let the public know what is our science curriculum and what are we learning.
The objective of the Lower Secondary Science Curriculum in Hwa Chong Institution (or HCI LSS) is to bridge the theoretical knowledge learnt in science to that of the real world, and especially in developments of recent cutting edge research and contemporary science. Similar to the “Science Curriculum Framework” by the Ministry of Education (MOE) in 2008, “INtegrated Science” emphasizes the holistic acquisition of knowledge, skills, values and applications embedded in the 4 unique “Science IN” features which is congruent to our Parallel Curriculum Model (or PCM).



"Based on the 4 “Science IN” features, the objectives of the HCI LSS Curriculum are to enable students to:

• acquire content knowledge and understanding of Science.
• expose students to recent cutting edge research and contemporary science.
• develop essential skills, learning through authentic experiences and practice.
• monitor their own learning, thinking process and related affective attributes.

Hence, students will be developed to do various activities relating to the field of science research and exposed to contemporary developments. Hence, teachers will be applying their professional judgment to use a variety of resources, ideas and strategies to effectively complement a students’ curiosity about the world to how it functions."

-quoted from hci wikis-

Basic stuff.....

Measuring Area

Use formulae for regular figures e.g. cylinder, square pyramid et.c.
Square = length x length
Rectangle = Length x breath
Triangle = ½ x base x height
Circle = πr(square)

For irregular figures:
• Use estimation.
• Done by dividing the figure into small squares.
• The area of each square has to be first defined.
• If more than half the area of the square is occupied, it will be taken as part of the
reading.
• If less than half the area of the square is occupied, it will not be taken as part of the
reading.
• The smaller the squares, the greater the accuracy.

Micrometer Screw Gauge

The micrometer screw gauge (commonly shortened to micrometer) can measure lengths to accuracy up to 0.001 cm or 0.01 mm. This instrument is used to measure very short lengths such as the diameter of a thin wire or the thickness of paper.


The micrometer has two scales: the main scale on the sleeve and the circular scale on the thimble. One complete turn of the thimble moves the spindle by 0.50 mm. There are 50 divisions on the thimble.
Hence each division represents a distance of (0.50 ÷ 50)

mm = 0.01 mm.  

A micrometer therefore allows us to measure accurately up to 0.01 mm.

Method of Reading: 
- Read the main scale reading at the edge of the thimble. 
- Next, take the thimble reading opposite the datum line of the main scale. 
- The reading is found by adding the main scale reading to the thimble reading. 

TAKE NOTE---->

The screw should never be tightened too much. As such, the micrometers are fitted with a ratchet to avoid this, but in older models it is possible to damage the screw by over tightening.  

It is also a good experimental technique to clean the ends of the anvil and spindle before making a measurement. Any dirt on either of these surfaces could affect the reading. As this measures stuff as precise as 0.01mm, and the dirt is something like this length, so it would affect the accuracy of the experiment no matter what. 

Vernier Calipers

How to Measure using vernier calipers:

- Make sure the jaws are adjusted to touch the opposite sides whose distance is to be
measured.
- Place the calipers on a ruler to measure the distance between the jaws.
 

As the metre rule or measuring tape are only accurate to 0.1 cm. For greater precision, we
need special instruments: vernier calipers and micrometer screw gauge.

Introduction

The vernier calipers is used to measure lengths accurately to 0.01 cm or 0.1 mm. Readings can be read off using the instrument itself without using a ruler. This instrument comprises of 1 external calipers, 1 internal calipers and a tail for measuring depths.

Method of reading

1. Close the jaws and ensure that the zeros present on both the vernier and main scale 

form a straight line. 

2. Jaws are then adjusted and clamped onto the object to be measured. 

3. Note the reading on the main scale. 

Note the reading on the vernier scale. 

4. Final reading = main scale reading + vernier scale reading. 

 

Zero error: 

Occurs when the zero marks on vernier scale and main scale failed to align when the jaws are completely closed completely. 

Positive zero error: 

Initial Reading (without taking account of zero error) is overestimated as the zero mark of the vernier scale lies on the right of the main scale.  

Hence Actual reading = Initial reading - Zero error

 

 

Negative zero error:

 Initial Reading (without taking account of zero error) is 

underestimated as the zero mark of vernier scale lies on the left 

of the main scale.  

Hence actual reading = Initial reading + zero error

 

  

As a precaution, always REMEMBER TO CHECK FOR ZERO ERROR 

BEFORE USE OF VERNIER CALLIPERS

. 

Wondering.....

How do we measure objects without flat sides? Is that the question that is rousing deep within you? Like sphere, how you measure the diameter ACCURATELY? It will be rather difficult to use a ruler to make measurements on objects with curved or uneven surfaces. In this situation, a pair of engineer’s calipers can be used which consist of a pair of steel jaws hinged at the base.


An external calipers used to measure the external diameter, thickness of length.
An internal calipers used to measure the internal diameter, thickness of length.


ALL THESE CAN BE MEASURED USING CALIPERS!

 

Metre Rule

The metre rule can measure length up to a maximum of 1 metre and is usually made of wood
or metal. The smallest division is 1 mm or 0.1 cm and hence the accuracy of this instrument
is up to 0.5 mm.

In using the metre rule, you have to avoid parallax errors. Parallax errors occur due to the 

wrong positioning of the eye or the object is not at the same level as the markings of the 

scale. The eye position must be vertical or perpendicular to the mark to be read or else 

parallax error may occur. 

Important!!!!!!!!!!!!

Readings on the metre rule cannot be more than 1 decimal place measured in "cm" for Precision

   >Examples: 4.50 cm or 3.05 cm is correct but not 4.47 cm or 3.11 cm 

But still there are ways to avoid parallax errors:

>Use a thin ruler 

>Ensure that eye is placed vertically above the mark to be read 

>One way to improve accuracy of the experiment is take several (3 to 4) readings and 

find the average.   

Term 1 Week 6~9/10

Term 1 Week 6~9/10

We started on a new topic: Measurements.
Mr Sim is away for some reasons, so a relief teacher came in to relief us, which i think i quite good and kind as he let me copy the notes from his powerpoint even after the lesson(meaning he sacrificed his resting time for me)
We were taught how to use the measuring equipments: Metre Rule, Vernier Calipers, Micrometer Screw Gauge 

Week 4~5

Well, Mr Sim continue on the "Science as an Inquiry" topic:D

He also bring as to the science lab to do some hands-on experiment:D

Term 1 Week 2~4

Science As an Inquiry
I learn that the elements of science are attitudes, process and Methods, and finally products. I know that being a scientist and a student, one must posses these skills and techniques to become a good scientist/student(learning science).
Attitude is the  willingness to modify their own views in the face of new evidence,respect for ideas of other and not to jump to conclusions without investigating(through experiments and all) Scepticism for generalisations not based on verifiable (repeatable) observations.  Being objectivity by seeking data and information to validate observations or explanations.  Also, having the interest and enjoyment in studying the marvels of nature.

Process skills involve: observe, classify, communicate, measure, infer, estimate and predict, well of course logically, and also proving it. We must observe carefully and measuring accurately. And also Communicate with our working partner effectively. Making Inference and developing a hypothesis.Effective Planning or designing experiments to test the hypothesis.

Products of Science are the info and ideas of science that have been recorded as scientific knowledge. Scientists build on what other scientists have discovered. Video conferencing, the Internet and cloning of animals are all products of technology. 

But then with science there is benefits, but also the abusing of science knowledge. Science can help to prolong one's lifespan and also improve healthcare, which kind of prolong-ing the lifespan of one. It can help to improve one's lifestyle and help to make things more convenient and comfortable. Oh, and one more benefits is that it helps to connect people around us through the virtual world, on social platforms, like facebook and twitter. But then science can cause troubles too, for example: polluting the environment, destroying life and agriculture(nuclear incidents) and also the most concerned: depleting of natural resources), thus upsetting the law of nature! Like when people clear out forests for development and they usually clear the forests out through burning, which pollute the environment and contributing to global warming, as the carbon dioxide given out is one of the greenhouse gases. These gases is then trapped within our atmosphere, warming up the Earth.

Well, of course, Science cannot give life to non-living object(but can cure an ill person), unable forecast future events. And also, explain matters relating to religions, like gods deities or myths. And neither helping us return to the past or go to the future(although my dream, since young, was to build a time machine:P). 

 

On this lessons, Mr Sim, our science/form teacher, teaches us how science is applied to the jobs, requiring science. We were also given an activity, on if we are given a chance to interview any scientist from either the past or present, what will we say and ask. Mr Sim also brief us through the safety measures and the rules while being in the science laboratory, about the DOs and DON'Ts. We are also given an activity to help us apply what we have learnt about the rules of the science laboratory. There is a picture, showing a scene of a lab, filled with students doing experiments, and we are required to spot out which student in the picture have violate the rules or which student obey the rules. Mr Sim, teaches us about the lab's tools and apparatus, on why are the apparatus model that way and how to use it and on which occasions should we use these apparatus. And we are also taught of the Bunsen burner, what is a non-luminous flame and what is a luminous flame, how to characterize them.

 Luminous flame   

 -occurs when the air-holes are 

     closed and very little air is 

   allowed to mix with the gas 

-carbon particles are on apparatus            

 - orange 

  - appears flickering and unsteady 

 - not very hot

Non-Luminous flame           

-produced when the air-holes are open  

-sufficient air for gas to burn completely 

 - occurs when the air-holes are 

open, allowing air into the burner 

- blue 

- burns steadily 

- hotter than the luminous flame 

- hottest part of the flame is just 

 above the tip of the blue zone. 

There will also be strikebacks if you are not careful! And you must hold the boiling stuff at the right position.

so be careful whenever handling Bunsen burner.