Light

In our daily life, we are familiar with the term of light. Anyway, do you know what the definition of it? The scientists had argued about the nature of light.

Newton versus Thomas Young

Newton believed that the nature of light was particles. On the contrary, Thomas Young believed that light travelled as waves.

Albert Einstein

By his photoelectric effect, he showed that the light can act like waves and particles.

Observing the Interference Fringes of Light

We need a beam of laser light through two slits. After it passes through the slits, it will spreads out into the space beyond.

How does this result obtained?

Where there is a bright fringe, the lights are in step with each other when they leave the slits. They interfere constructively. Where there is a dark fringe, the lights are no longer in step. They interfere destructively.

Thomas Young's Double Slits

Determining the Wavelength

a = slit separation

x = fringe separation

D = slit-to-screen distance