Entry #3

Physics Journal 3

Measurement
Significant Figures

When recording measurements......

1 Take note of the precision of a measuring instrument.
e.g. with a vernier caliper, the fixed scale of the vernier caliper may either have the units of 1mm, or 1cm. BE CAREFUL WHEN READING!!!!! (Happened to me once. :p)

2 Read to the smallest 1/2 division of the smallest scale.
e.g. when the smallest scale on your ruler is 1mm, the smallest value you should read to is 1/2mm.

Now for length measurements.
There are 3 kinds of apparatus (to the smallest scale)
Meter rule (0.1cm), Micrometer screw gauge (0.001cm) and Vernier caliper (0.01cm).

Intro to the micrometer screw gauge 

*Take the reading at the point where a line on the vernier scale is aligned with the fixed scale
*Don't take 1/2 division for the smallest division
*If thimble is right on the datum, round it down to the nearest whole.

Zero error also applies for the micrometer screw gauge (msg)
Here's the example for the Vernier caliper:

Significant figures


Rules for Significant figures:

-All non-zero digits are Sig. Figs.
-All final zeros after the decimal point are significant
-Zeroes between non-zero digits are always significant
-Zeros used before the first non-zero digit are not significant
-All the zeroes that come after a sig fig may or may not be significant if there is no decimal point

Thoughts: I find the topic on significant figures rather confusing at first as to when and how to use them. :|

Entry #2

Physics Journal 2

Prefixes
Scientific Notation

Prefixes
What is a prefix?
Say, the base quantity is meter.
A common prefix for this unit is centi.
Put them together and you get centimeter.
In other words, centi is the prefix for the base quantity meter.


Table of common prefixes 

Scientific notation


The standard form of Scientific notation: Nx10e (Ten to the power of e, cause idk how to make the e small ><) 
N Being a number between 1 and 10
e Being the Index/exponent that can vary.


e.g.
Express 4660.0 in scientific notation.
To make it a number between 1 and 10, we move the decimal place (d.p.) to the left.
Therefore 4660.0 becomes 4.66. Since the d.p. has been moved by 3 places, 4660.0's index notation should be written this way: 4.66 X 103 (10 to the power of 3. )


Thoughts: I find this rather straight forward but without regular revision, it is easy to forget the rules on how to get the Scientific notation. :)

Entry #1

Physics Journal #1

What I have learnt: 

                               Types of Quantities

                               How to calculate Formulae

Physical Quantities             Base Quantities              Derived Quantities

Temperature                       Length                            Area

Time                                  Time                                Volume

Distance                             Mass                               Speed

Weight                               Temperature                   Acceleration

                                           Electric Current              Density

                                          Amt of Substance

                                          Luminous Intensity

Table of Values and how to get Derived Quantities

How I feel: I feel rather happy that I am managing physics quite well, and I get a feeling of accomplishment when I manage to get the calculations correct. ^^

Other comments: I feel that I should be more careful as I can still make careless mistakes in the calculations.  ^^’||