Why Does the Bright Patch From a Window Slide Across the Floor?

What Crafty Clover says in this video

Intro

Hi there, curious minds! I'm Crafty Clover! Let's discover something amazing. Why does the bright patch from a window slide across the floor?

The Big Idea

The Earth is spinning, so the Sun seems to move across the sky. The angle of the light through your window changes, and the bright patch slides across the floor.

Spinning Earth

Step one: Earth is spinning. It turns around once every day, so the Sun seems to travel across the sky. The Sun is not really moving.

Changing Angle

Step two: the angle of the light changes. As the Sun appears to move, the sunbeam through the window comes in at a new angle. So the shape and place of the patch change slowly through the day.

Sliding Patch

Step three: the bright patch slides. In the morning it lands near one wall, and later in the afternoon it has moved toward the other side of the room. A sundial uses the same idea to tell the time.

A Closer Look

Let's take a closer look! First, Earth spins around. That makes the Sun seem to move across the sky. So the light through the window changes angle. And the bright patch slides across the floor. A moving patch of sun is a clock you can watch!

Quick Facts

Quick facts! A sundial uses the same idea to tell time. The Sun seems to move because Earth spins. A spot of light can travel across a whole room in a day. Never look straight at the Sun through a window.

Think Like a Scientist

Now, think like a scientist! Stick a piece of tape at the edge of a sunny patch on the floor. Mark the time on the tape. Check an hour later and mark the new spot. How far did the light patch travel?

Outro

The bright patch slides because Earth spins and the Sun seems to move. Science is amazing! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!