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Good morning! Ready to start the week? Well, we got natural science, last week we were talking about sound, and this week we talk about light. Pay attention!

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Light sources produce light energy, and without light energy we wouldn't be able to see anything.

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We got two main types that are artificial and natural. Artificial light sources are man-made, like us, and natural light sources are found in nature.

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examples of natural light sources the most important the Sun other examples

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are linings during a storm or some animals like fireflies all right

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artificial light sources examples a candle fireworks you like them okay the

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characteristics of lights the first one speeds light travels very fast about

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300,000 kilometers per second. This is called the speed of light and is faster than sound.

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important light travels in straight lines called rays. Straight lines, not the

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curved waves we see with sound. It's different. really appears white to us, but it's

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really made up of all the different colors. And we got three possibilities when a light

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becomes in contact with an object. It can be absorbed, it can be reflected, or can

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be refracted. Materials can be transparent when all light passes

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through, they can be translucent when some light passes through, and opaque

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when no light passes through. The second possibility we were talking about was

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that light is reflected, so we talk about reflection. It occurs when rays of light

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are not absorbed by an object and bounce off instead we have smooth surface light

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reflect in the same direction however on rough surface light reflects in all

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directions the most famous example of reflection are the mirrors okay now

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third possibility we're talking that light refracts the process called

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refraction it occurs when light travels in a straight line but it passes through

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a medium with a different density it changes direction example look at this

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pencil water has got a different density so that's why we see that light changes

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the direction famous examples lenses and of course the rainbow these are examples

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of refraction well this is the lights if something is not clear please ask your

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teacher and well I'll see you soon goodbye