Hey!!!
Today we learnt about Series Circuit...
Do you know what will happen if resistors are connected in Series.....???
It will start to have :
. Overall resistance increases....
. Current decreases
. Bulb is dimmer....
(Less bright)


Next is Parallel Circuit...

:Parallel circuit has more than one path for current to flow....

:Current from battery=sum of current in separate paths....

: Voltages are equal across the branches....

Hm...

Let's see, there are two bridges connected in parallel...

If one of the bridges breaks, can the runner still reach the other side...???

Well, the answer is YES!

The advantage:

-Current become bigger....

-If lightbulb cannot work, the other lightbulb still light up...

But WAIIIIIIIIIIT...

Series circuit has only ONE path for current to flow unlike the parallel circuit...

Current is the same at any point....

Total resistance for two resistors in series are:

R=R1+R2

This video is about Series Circuit.....
Have fun watching....

Today's Lesson on Series & Parallel Circuit during Science Lesson on 25 August 2009

Today's lesson, we learnt about Series & Parallel Circuit.













THIS IS AN EXAMPLE OF A SERIES CIRCUIT :

• Series circuit has only ONE PATH for current to flow through


• Current is the same at any point.


• This is the formula for resistance for teo resistors in series:

- R = R1 + R2

One disadvantage is, if one of the light bulb can't work, current will stop flowing.

WHAT HAPPEN IF THE RESISTORS ARE CONNECTED IN...

• Overall resistance increases.


• Current decreases.


• Bulb is dimmer (less bright).

A series circuit has more than one resistor (anything that uses electricity to do work) and gets its name from only having one path for the charges to move along. Charges must move in "series" first going to one resistor then the next. If one of the items in the circuit is broken then no charge will move through the circuit because there is only one path. There is no alternative route. Old style electric holiday lights were often wired in series. If one bulb burned out, the whole string of lights went off.

Next I will talk about PARALLEL CIRCUIT:

• Parallel circuit has MORE THAN ONE PATH for current to flow


• Current from battery = sum of current in separate path (like the picture below)

• Voltages are equal across the branches.
• Parallel circuit has more than one path for current to flow.

The advantages are current become bigger and if a light bulb cannot work, other light bulb would still light up...

The formula for parallel circuit is Current from battery = sum of current in separate paths ( P = Q + R )

Total resistance, R, (1/R1 + 1/R2)-1 or either 1/R = 1/R1 + 1/R2

What happen if resistors are connected in...

• Overall resistance decreases.
• Current increases.
• bulb is much more brighter.

A parallel circuit has more than one resistor (anything that uses electricity to do work) and gets its name from having multiple (parallel) paths to move along . Charges can move through any of several paths. If one of the items in the circuit is broken then no charge will move through that path, but other paths will continue to have charges flow through them. Parallel circuits are found in most household electrical wiring. This is done so that lights don't stop working just because you turned your TV off.

Learn about Heat Transfer and Its Consequences

Today we learn about heat.






Heat is used in daily life..There are 3 processes that are Conduction, Convectiion and Radiation.

* Conduction is the transfer of heat energy through a material to protect it from the hot to the cold regions without any visible movement or flow of the material.

* There are to substances in life that are the conductor and insulator...

• The insuulators are for example are water, glass, plastic or wood etc.



• The conductors are for examples are metal such as brass, steel,invar etc.

Convection is the transfer of heat from one part of the fluid to another by the circulating movement of the fluid itself. Radiation transfer heat in the form of electromagnetic waves and does not need a medium.

The meaning of the words is as shown below :

• CONVECTION - MOVING MOLECULES TRANSFER HEAT THROUGH LIQUID OR GAS



• CONDUCTION - HEAT MOVES THROUGH HOT SURFACE ONTO HOT TO COLD SURFACE



• RADIATION - TRANSFER HEAT IN THE FORM OF ELECTROMAGNETIC WAVES .

** TO REDUCE THE LOSS OR GAIN HEAT BY RADIATION , AN OBJECT SHOULD HAVE A SHINY, SILVERY OR/AND SMOOTH SURFACE TO HAVE AN INCREASE OF THE LOSS OR GAIN HEAT BY THE RADIATION AROUND THE SURROUNDING BY HAVING A DULL, BLACK AND HAVE A VERY ROUGH SURFACE.

CONVECTION GIVES RISE TO SEA AND LAND BREEZES. DURING THE DAY, THE LANDS HEAT UP FASTER AND REACHES A HIGHER TEMPERATURE MUCH MORE EASILY. THE AIR OVE R THE LAND GETS HEATED UP, EXPANDS AND WOULD BECOMES DENSER AND WOULD RISE. THE FLOW OF COOL AIR FROM THE SEA TOWARDS THE LAND THAT WOULD PRODUCE A SEA BREEZE.

THIS IS AN EXAMPLE OF A SEA BREEEZE..

A vacuum/ thermos flask keep things close to their original temperature by reducing the transfer of heat between the flask and its surrounding. Heat is obtained from various sources such as the SUN, burning fuels, and electrical heating appliances. Solar heaters are used to absorb heat from the Sun. It is also an easier way to save electricity !! 'o'

Changes of States

Today we learn about changes of states....
There are melting,freezing,boiling and condensation

MELTING :

Melting is the changes of change of state from the SOLID state to the LIQUId state..
(HEHE..)


BOILING:

Boiling is about a change of state from LIQUID state to GAS state where there is a change of tempereture..


*** I LIKE WHEN MY SCIENCE TEACHER THOUGHT ABOUT RIVET. THESE ARE SOME OF THE E.G:

contraction and expansion

gtg ..

What We've Learnt....

Today we learnt a lot of things..
Not sure where to start..
Hm...
We learn about Riveting..
Melting...

Boiling..
Freezing...
Condensation...
Riveting...
Rivet is a permanent mechanical fastener.
It tightens two metals together ..
A cool rivet:
2 metal plates tighten together when
rivet contracts...

Melting**
+ Change of state from solid to liquid without a change
in temperature....
E.G. Ice melts at 0 degree celcius........
Condensation.....
Condensation is the change of the physical state of aggregation (or simply state) of matter from gaseous phase into liquid phase.

Boiling........

Boiling, a type of phase transition, is the rapid vaporization of a liquid, which typically occurs when a liquid is heated to its boiling point, the temperature at which the vapor pressure of the liquid is equal to the pressure exerted on the liquid by the surrounding environmental pressure.

Freezing............
Freezing or solidification is the process in which a liquid turns into a solid when cold enough. Melting, the process of turning a solid to a liquid, is almost the exact opposite of freezing.
All known liquids freezes and their temperature has fixed points which is 0 degree celcius....
Okay, got to go now..
Toodlez...
But wait!!!
Got pics for u guys to c..

+++++ Liquid In Glass++

***************** * The physical property of liquid in glass*
*Volume of fixed mass of liquid*
** The Physical property of Thermocouple**
** Amount of electromotive force
***( Electric Current)**
%%% The Physical property of Bimetallic Thermometer%%%%
++ Unequal expansion and contraction of two types
of metals.....
That's all folks..
$anc#!ko & Nad!a

Thermocouple..

Things that We've Learn

****************************** Temperature and Heat**********************************

Hey you guys!!!
Today, in class, me and my friend Farah, learn new things that is Temperature and the usage of thermometer...

So, what is Temperature..?
Exactly.. there are more than 1 thermometer use...
It is the measure of hotness/coldness of an object...
Hm..
Do they use any instrument to measure.....?
YES! It is thermometer...
A thermometer has 2 physical properties that consists of volume and electromotive force...(Voltage)..


Every thermometer is needed a fixed point for a standard so that other temperatures can be defined...
The SI unit... for a temperature is Kelvin... (K)
Hey!!!
Kelvin!!!
That's our friend's name...