Why Can You See Your Room Reflected in a Window at Night?

What Crafty Clover says in this video

Intro

Hi there, curious minds! I'm Crafty Clover! Let's discover something amazing. Why can you see your room reflected in a window at night?

The Big Idea

Window glass lets most light through, but it also reflects a little, like a very faint mirror. In the daytime, the light from outside is much stronger than the reflection. At night, the room is brighter than the dark outside, so the reflection wins.

Mostly See-Through

Step one: mostly see-through. Most light goes straight through window glass. That is why you can look outside in the daytime.

A Faint Reflection

Step two: a faint reflection. About 4 percent of the light bounces off each glass surface. That is a small amount, but it is always there.

Night Switch

Step three: the night switch. When it gets dark outside, almost no light comes in through the glass. Your bright room wins, and the reflection stands out.

A Closer Look

Let's take a closer look! In the daytime, bright outdoor light shines through. At night, the outside is dark. Your room lights make a bright reflection. So you see your room floating in the glass.

Quick Facts

Quick facts! Shop windows are easiest to see into when it is bright outside. Switching off the room lights makes the reflection fade. Cupping your hands against the glass blocks the room light. Stay inside, and do not go outside alone in the dark.

Think Like a Scientist

Now, think like a scientist! At night, look at a window from inside with the room lights on. Then switch off the lights, or cup your hands around your eyes against the glass. What changes? Do not go outside alone in the dark.

Outro

At night, window glass shows your room like a faint mirror. Science is amazing! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!