Estimate the number of photons emitted by the Sun in a second.The power output from the Sun is 4 $\times$ 10²⁶ W and assume that the average wavelength of each photon is 550 nm. A)10²⁶ B)10⁴⁵ C)10²³ D)10²⁸ E)none of the above

Question

Quizplus · Accepted Answer

The energy of a photon can be calculated using the relationship E = hc/λ, where h is Planck's constant, c is the speed of light, and λ is the wavelength. 
Plugging in the given values, we get E = (6.626 x 10^-34 J s) (3.0 x 10^8 m/s) / (550 x 10^-9 m) = 3.61 x 10^-19 J. 
The number of photons emitted per second can be calculated by dividing the total power output by the energy of a single photon: 
(4 x 10^26 W) / (3.61 x 10^-19 J/photon) ≈ 1.11 x 10^45 photons/s.

Rounding up to two significant figures, the answer is 1.1 x 10^45 photons/s. The only option that is close to this value is B (1.45 x 10^45 photons/s).

Estimate the Number of Photons Emitted by the Sun in a Second.The