Yeti explains plant color further

_Elsa_

“So what makes chlorophyll green?” asks David. 

‘Every object on Earth has its own color. The light from the sun appears white but is actually made up of a full spectrum of colors: red, orange, yellow, green, blue, indigo, and violet. When white light hits an object, the object absorbs some colors and reflects others. When we look at an object, the color we see is the color the object reflects. The sky absorbs all the colors except blue, which it reflects. This is why the sky appears blue on a sunny day. 

David is not sure that he really understands it fully so Yeti takes it a step further.

“Do you go outside with your mother to play ball?” asks Yeti.

David nods his head yes. Yeti now offers him an explanation that he had found online.

‘The red rubber ball absorbs all the wavelengths in white light except red. As you watch the red ball bounce along the ground, your eyes see the ball reflecting red light. Your eyes send this information to your brain, which tells you the ball is red.

Similarly, grass appears green because it absorbs all the wavelengths of white light except green. Green is reflected off the grass. When the green wavelength reaches our eyes, we see grass as green.’ (Source)

David seems to be satisfied with Yeti’s explanation. He looks around to see if he can ask him another question.

“Why do birds fly,” asks David.

Yeti has the answer for him but since it might be too complicated for David to understand he goes to Google to find a simple explanation.

‘Bird bodies are made to fly. They have light bones, strong legs, and specially shaped wings. Flying helps birds get away from animals that want to eat them, and makes them better hunters, too. Flying also helps them travel from cold places to warm places, called migration (my-GRAY-shun).

But why?

A bird uses its legs to push off the ground into the air. That’s called thrust. It flaps its wings to stay in the air. That’s called lift. When you put thrust and lift together, a bird flies. Its wings also have a curved shape, like an upside-down spoon. This shape helps the air move above and below the wings and keep the bird in the air. Birds’ feathers also help them fly. Air rushes through the feathers, creating more lift. 

But why?

Birds don’t always have to flap their wings to fly. Once they’re up high in the sky, they can also glide, which is kind of like getting a free ride on the air. They only have to flap their wings once in a while. They can also let a jet of air push them up even higher, to the tops of really tall trees. That’s called soaring. Different birds can fly in different ways. Sea birds can dive really fast into the ocean to catch fish. Hummingbirds can flap their wings so fast all you see is a blur. Every time you ride in an airplane, you can thank birds for showing humans how to fly.’ (Source)

David seems to be satisfied with the explanation. Rachel just looks at Yeti with a look of how do you have the patience?

Let’s continue - Here comes some weather questions!

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Start at the beginning of the main story – Why … But WHY?

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