Sci Blog entries

 In this video, it shows how electricity flows in a parallel circuits. In the circuit shown in the video, there are two resistors in the circuit. During the video, the blue arrow ( Current flowing ) reduces in size upon reaching the junction where it splits into 2 directions. 

Electricity is a form of energy and also the flow of electric charges. when the electric charges flow,they carry energy known as  electrical energy or electricity.In a parallel circuit,the electrical components are connected in different loops.There is more than 1 path for the electric charges to flow in the circuit.A break or a faulty component in 1 loop of the circuit does not prevent the current flow in the other loops.Electric current is the rate at which the electric charges flow. It is a measure of the amount of electric charges flowing through a particular point in a circuit.The symbol electic current is I. The SI unit is Ampere(A).Electric current flowing in a circuit is measured by an AMMETER.In a parallel circuit,the potential difference(p.d) across all the branches of a network is the same Ohm's law states that the current in a circuit is inversely proportional to the circuit resistance. This fact is true in both series and parallel circuits.

There is a single path for current in a series circuit. The amount of current is determined by the total resistance of the circuit and the applied voltage. In a parallel circuit the source current divides among the available paths..

-Hidayah 2e3

Why is lighting attracted to metal?

It happened because static electricity builds up between rain clouds, or between rain clouds and the ground. Lightning bolts can carry up to 100 million volts of electricity. Lightning bolts can jump from cloud to cloud or from a cloud to the ground. Lightning strikes on high ground or objects that stick out of the ground, like poles and trees. Metal is the best conductor of electricity, so lightning is easily attracted to metal objects.Lightning can kill ,it is better to stay indoor.How do you know lighting is near or far?Count the seconds between the bolt and thunder.If it is less than 30 seconds ,the lightning is within 10 a miles .Read more at Suite101: Flash and Rumble PGp
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Tan Kai Chin

Wei Cong.

You have probably heard two different ways of talking about light:

* There is­ the "particle" theory, expressed in part by the word photon.
* There is the "wave" theory, expressed by the term light wave.

­From the time of the ancient Greeks, people have thought of light as a stream of tiny particles. After all, light travels in straight lines and bounces off a mirror much like a ball bouncing off a wall. No one had actually seen particles of light, but even now it's easy to explain why that might be. The particles could be too small, or moving too fast, to be seen, or perhaps our eyes see right through them.

The idea of the light wave came from Christian Huygens, who proposed in the late 1600s that light acted like a wave instead of a stream of particles. In 1807, Thomas Young backed up Huygens' theory by showing that when light passes through a very narrow opening, it can spread out, and interfere with light passing through another opening. Young shined a light through a very narrow slit. What he saw was a bright bar of light that corresponded to the slit. But that was not all he saw. Young also perceived additional light, not as bright, in the areas around the bar. If light were a stream of particles, this additional light would not have been there. This experiment suggested that light spread out like a wave. In fact, a beam of light radiates outward at all times.

Albert Einstein advanced the theory of light further in 1905. Einstein considered the photoelectric effect, in which ultraviolet light hits a surface and causes electrons to be emitted from the surface. Einstein's explanation for this was that light was made up of a stream of energy packets called photons.

Modern physicists believe that light can behave as both a particle and a wave, but they also recognize that either view is a simple explanation for something more complex. In this article, we will talk about light as waves, because this provides the best explanation for most of the phenomena our eyes can see.

Wei Cong

Light
Whether its source is the Sun, a flashlight, or a fluorescent bulb overhead, light is a form of energy that is common in our everyday lives. One of light's characteristic properties is that, in a transparent medium like air, glass, or still water, it travels in a straight line.

Light exhibits characteristics of both waves and particles, the latter of which are described as packets of energy called photons. These waves, or photons, travel in narrow beams called rays. Only when light rays move from one medium to another, such as from air to water, are their linear paths altered.

So how do we know that light travels in a straight line? Because of the nature of light—for example, it moves in a vacuum at a speed of more than 186,000 miles per second, or 300,000 kilometers per second—it is, for all practical purposes, impossible to observe individual particles. But evidence of its linear pathway can be seen in a number of demonstrations.

Wei Cong

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