Hello there! Let's learn about "The Sun and the Ground" together!
Hello everyone! Today, we're going to study the wonders of the "Sun," which is essential to our daily lives, and the "ground" that receives its light.
Let’s solve questions like "Why does my shadow move?" and "What’s the difference between sunny spots and shady spots?" one by one.
If you feel like science is a bit tricky, don't worry! We’ll take it slow and use familiar examples along the way.
1. The Mysterious Relationship Between the Sun and Shadows
Have you ever noticed your shadow while playing outside? Shadows have a very close relationship with the Sun.
The Direction of the Sun and Shadows
A shadow is always formed in the opposite direction of the Sun.
For example, when the Sun is in the "East," your shadow stretches to the "West." When the Sun is in the "South," your shadow stretches to the "North."
【Key Point: How Shadows are Formed】
Shadows are created when sunlight is blocked by an object. So, just remember that the Sun and your shadow are always "back-to-back" buddies!
Shadow Length and the Height of the Sun
The length of a shadow doesn't stay the same throughout the day.
・Morning and Evening: The Sun is low in the sky, so shadows become long.
・Around Noon: The Sun is high in the sky, so shadows become short.
★A Quick Tip for Remembering:
Try shining a flashlight on a toy. If you shine it from directly above, the shadow gets small, but if you shine it from the side, the shadow stretches out long. It's exactly the same thing!
【Common Mistake】
Some people mistakenly think that "a shadow stretches toward the Sun," but remember that a shadow always stretches away from the Sun. When you're observing, it's easy to see if you stand with your back to the Sun.
Chapter 1 Summary:
・Shadows form on the opposite side of the Sun.
・When the Sun is high, the shadow is short; when the Sun is low, the shadow is long.
2. The Sun's Movement and Direction
How does the Sun move across the sky? To understand this, it's important to know the cardinal directions (East, West, South, and North).
How to Use a Compass
We use a "compass" to find directions. Let’s learn the steps:
1. Place the compass on a flat surface.
2. Wait for the needle to stop (the red end of the needle always points North).
3. Align the red tip of the needle with the "N" (North) mark on the compass dial.
The Sun's Movement Throughout the Day
Throughout the day, the Sun moves in the following way:
Rises in the East → Passes through the South → Sets in the West
【Did You Know?】
The Sun reaches its highest point in the sky when it is directly to the "South." This is called "solar noon" (or culmination). At this time, your shadow is at its shortest length of the day and points true North.
Chapter 2 Summary:
・The Sun moves in the order of East → South → West.
・The red needle of a compass points to the North.
3. Sunny Spots vs. Shady Spots
What differences are there in the condition of the ground between places where sunlight hits (sunny spots) and places where it doesn't (shady spots)?
Differences in Warmth (Temperature)
If you touch the ground, you'll find that sunny spots are warm, while shady spots are cool.
This is because the sunlight is warming the ground.
How to Use a Thermometer Correctly
When measuring ground temperature, keep these points in mind:
・Bury the bulb (the bottom part containing the liquid) slightly into the ground.
・Create a shade using paper or a similar object so that direct sunlight doesn't hit the thermometer.
・When reading the scale, look at the top of the liquid straight on from the side.
【Important Tip!】
If you let the thermometer sit in direct sunlight, you'll be measuring the "heat of the sunlight" instead of the ground temperature, so the reading won't be accurate. Be careful!
Differences in Moisture
Look at the ground after it rains. Sunny spots dry quickly, but shady spots stay damp for a long time. Sunlight has the power to evaporate water and dry the ground.
Chapter 3 Summary:
・Sunny spots are warmer and dry faster than shady spots.
・When measuring temperature, do not let direct sunlight hit the thermometer.
Closing: Enjoy Your Science Observations!
The best way to learn about "The Sun and the Ground" isn't just by reading a textbook, but by actually going outside and seeing it with your own eyes.
You might feel confused at first, thinking, "Wait, which way is East again?" but that's okay. Just remember that the direction the Sun rises every morning is East, and you'll naturally get better at finding your way around.
Feel the Sun’s great energy as you observe how your shadow's length changes and notice the difference in temperature on the ground!