A heat lamp produces 22.5 watts of power at a wavelength of 6.0 {\rm \mu m}.
How many photons are emitted per second? 1{watt}} = 1 J/s
i got 7.02*10^20 but that is incorrect, can you help?
We may be able to help if you let us in on what {\rm \mu m} stands for.
it stands for Mu/meter
To calculate the number of photons emitted per second, you need to use the formula:
Number of photons = (Power / Energy of a photon) * (1 second)
First, let's calculate the energy of a single photon using the formula:
Energy of a photon = (Planck's constant * speed of light) / wavelength
Planck's constant (h) = 6.626 x 10^(-34) J·s (joule-seconds)
Speed of light (c) = 3.00 x 10^8 m/s (meters per second)
Wavelength = 6.0 μm = 6.0 x 10^(-6) m (meters)
Now, we can plug in these values:
Energy of a photon = (6.626 x 10^(-34) J·s * 3.00 x 10^8 m/s) / (6.0 x 10^(-6) m)
Calculating this, we get:
Energy of a photon ≈ 3.313 x 10^(-19) J (joules)
Next, we can calculate the number of photons emitted per second:
Number of photons = (Power / Energy of a photon) * (1 second)
Plugging in the values given:
Number of photons = (22.5 J/s) / (3.313 x 10^(-19) J) * (1 s)
Calculating this, we get:
Number of photons ≈ 6.78 x 10^20 photons per second
So, the correct answer is approximately 6.78 x 10^20 photons per second.