Watts to Photons Per Second Calculator

Formula

The formula to calculate the number of photons per second is:

\[ \text{PS} = \frac{W \times \lambda}{h} \]

Where:

PS is the number of photons per second.
W is the power of the light source in watts (W).
λ is the wavelength of the light (meters).
h is Planck’s constant (6.62607015 × 10^-34 m^2 kg / s).

What is Watts to Photons Per Second?

Watts to photons per second is a conversion factor used in physics to quantify the number of photons (light particles) emitted per second by a light source. The watt is a unit of power that measures the rate of energy conversion or transfer, while photons per second measures the number of photons emitted by a light source in one second. This conversion is particularly useful in fields such as quantum physics and photonics, where the behavior and properties of photons are studied.

Example Calculation

Let's consider an example:

Power (W): 10 watts
Wavelength (λ): 500 nm (5 × 10^-7 meters)

Using the formula to calculate the number of photons per second:

\[ \text{PS} = \frac{10 \times 5 \times 10^{-7}}{6.62607015 \times 10^{-34}} \approx 7.55 \times 10^{27} \text{ photons/second} \]

This means that the number of photons emitted per second for this scenario is approximately \(7.55 \times 10^{27}\) photons/second.