Question

Compare the speeds of light of wavelength 400 nm and 800 nm in vacuum.

Answer 1

Explanation:

Since light is an electromagnetic wave and it is the property of all the electromagnetic waves that they travel with same speed equal to 3×108 m/s in vacuum. Hence ratio of velocities of light of wavelength 4000 Ao and 8000 Ao in vacuum is 1:1.

Answer 2

Speed of 800 nm is same as speed of 400 nm light wavelength.

What is wavelength?

• Wavelength is defined as the length of one complete cycle of wave.
• Distance between two troughs is called a wavelength.
• Wave speed is independent of wavelength when the medium is vacuum.
• Low frequency light wave has greater wavelength.
• 400 nm to 800 nm is the wavelength range for visible light.
• Violet light ranges between 380 nm to 435 nm.
• Red light has wavelength around 700 nm.
• Both red and violet light has same velocity in vacuum.