Waves made with springs
Waves in spring When the left end of the spring vibrates, the vibration is transmitted to the other end. A spring can vibrate horizontally or vertically. Fixed-end reflection When a wave reflects off a fixed-end, the … more
Reflection
Optical Experiment Simulator
It is an optical experiment simulator consisting of a slit laser, lenses, and mirrors of various shapes. You can experiment by dragging the tool you want. Slit lasers are rotatable. Try dragging the red icon behind … more
Rainbow by Raindrops
A rainbow is a natural phenomenon where the dispersion of light is most visible. As you know, We can see a rainbow after rain because the water droplets bend and disperse the light. For example, if … more
Why does a CD reflect rainbow colors?
Adjust the wavelength of light to choose the color of light you want. If you adjust the angle of reflection correctly, the phases of the light may coincide. That angle is the angle at which light … more
See the Light
Even if the object does not shine by itself, why can we see it? The eye is the organ that feels light. Even if the object does not shine by itself, why can we see it? … more
Principle of Mirror
Why is the incident angle and the reflection angle the same? ‘Law of reflection’ has the word ‘law’ attached. ‘Law’ refers to a situation in which a natural phenomenon happens repeatedly and without exceptions. In other … more
Law of Reflection
The law of reflection Consider a light-ray incident on a plane mirror, the angle of reflection is equal to the incidence angle. This is the law of reflection. When looking at the end of the head … more
Total Internal Reflection and Optical Fiber
Total reflection and critical angle When light enters from a medium with a large refractive index to a medium with a small refractive index, the incident light does not pass through the boundary surface but is … more
Multiple Reflections
What is an image? Our eyes are designed to sense where the light came from. Even if the light didn’t actually originate there, if our eyes feel that way, our eyes say there’s an image there. … more