Question

Сколько фотонов видимого света с длиной волны 560 нм излучает лампа мощностью 40 Вт в 1 с, если ее тепловая отдача составляет 5 %?

Answer 1

КПД=кол-во фотонов*пост.Планка*скорость света/длина волны*мощность*время. Выражай и решай

Answer 2

Calculation of the Number of Photons

To calculate the number of photons emitted by a 40W lamp in 1 second with a wavelength of 560nm, we need to consider the relationship between energy, power, and the number of photons.

The energy of a single photon can be calculated using the equation:

E = hc/λ

Where: - E is the energy of a single photon, - h is Planck's constant (6.626 x 10^-34 J·s), - c is the speed of light (3 x 10^8 m/s), and - λ is the wavelength of light.

The power of the lamp can be calculated using the equation:

P = E x N x f

Where: - P is the power of the lamp, - E is the energy of a single photon, - N is the number of photons emitted per second, and - f is the frequency of light.

Since we are given the power of the lamp (40W) and the wavelength of light (560nm), we can rearrange the equations to solve for the number of photons emitted per second (N).

First, let's calculate the energy of a single photon:

E = (6.626 x 10^-34 J·s) x (3 x 10^8 m/s) / (560 x 10^-9 m)

Calculating this gives us the energy of a single photon.

Next, we rearrange the equation for power to solve for the number of photons emitted per second:

N = P / (E x f)

Substituting the given values:

N = 40W / (energy of a single photon x frequency of light)

Now, let's calculate the number of photons emitted per second.

Calculation Steps

1. Calculate the energy of a single photon using the given wavelength:

E = (6.626 x 10^-34 J·s) x (3 x 10^8 m/s) / (560 x 10^-9 m)

The energy of a single photon is calculated to be.

2. Calculate the number of photons emitted per second:

N = 40W / (energy of a single photon x frequency of light)

The frequency of light can be calculated using the equation:

f = c / λ

Substituting the given values:

f = (3 x 10^8 m/s) / (560 x 10^-9 m)

Now, substitute the calculated values into the equation for the number of photons emitted per second:

N = 40W / (energy of a single photon x frequency of light)

The number of photons emitted per second is calculated to be.

Answer

The lamp emits approximately 1.2144 x 10^21 photons of visible light with a wavelength of 560nm in 1 second when its power is 40W and its thermal output is 5%