i want few science questions for my jr.
Answers
Answer:
Can you please tell the name of chapter.
Answer:
Why is the sky blue?”
“Why can I sometimes see the moon during the day?”
“Why do birds fly south in the winter?”
Kids have so many science questions! Delight their curiosity with these answers to top science questions kids ask.
These simple answers are easy to understand, but tackle real science concepts to answer the how and why of our world.
blue skies1. Why is the sky blue?
The earth is surrounded by an atmosphere.
The atmosphere (i.e., air, one of the four elements) is a mixture of gasses, mostly nitrogen and oxygen.
The way the sun’s light travels through the atmosphere makes the sky look blue.
White light is made of several different colors, like you see in a rainbow. Each of these colors travel in a wave, but the wavelength (distance between the tops of each wave) varies. Red light has a long wavelength, while blue light has a much shorter wavelength.
wavelengths of colored lightWhen light from the sun enters our atmosphere, the waves collide with gas molecules. The longer wavelengths, like red and yellow, pass straight through and appear to us as “regular” sunlight.
Shorter wavelengths, like blue, bump into the gas molecules and scatter in different directions. Some of it still makes it through directly, but the rest is reflected back to our eyes from all directions, so the whole sky looks blue.
Use a slinky to demonstrate wave-length motion.
2. How much does the earth weigh?
The earth weighs 13,170,000,000,000,000,000,000,000 pounds. You can say this number like this: 13 octillion, 170 septillion. That’s A LOT more than a million, billion, or trillion pounds!
To put things in perspective:
One male African bush elephant weighs 13,000 pounds.
100 elephants would weigh 1,300,000 (one million, 300 thousand) pounds.
One million elephants would weigh 13,000,000,000 (13 trillion) pounds.
One trillion elephants–there are not even this many on earth–would weigh 13,000,000,000,000,000 (13 quintillion) pounds.
And still, earth weighs one billion times more than that!
How do scientists know how much the earth weighs? They study the gravitational pull the earth has on other objects, and use math to calculate how big the earth must be.