# B What is the amplitude of light?

#### Daniel Petka

Like every wave, light has a frequency and an amplitude. So far, I know that the frequency equals to the photon energy and the amplitude to the amount of photons. My question is: how big is that amplitude and does it matter?
Thanks for every reply

Related Quantum Physics News on Phys.org

#### vishal giri

frequency of the light can can be described as hν=E, SO FREQUENCY=E/h where h is joule s constant if we knw the photon energy

#### Daniel Petka

Thanks, vishal giri. I asked for the amplitude, though. The frequency is clear anyway...

#### mfb

Mentor
You can look at the strength of electric and magnetic fields. As an example, an intensity of 1 kW/m2 for a planar wave corresponds to peak values of about 400 V/m and 1.4 microTesla, give or take numerical prefactors that I forgot.

### Want to reply to this thread?

"What is the amplitude of light?"

### Physics Forums Values

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving