The energy efficiency of an incandescent light bulb (= the percentage of consumed power that is actually converted into radiated light) is typically around 5%. Suppose a certain brand of 75 W incandescent bulb emits light primarily at wavelength = 570 nm.

Calculate the total number of photons emitted by one of those bulbs if it has been shining for a 6-hour period.

4*10^22 photons

Explanation:

To find the number of photons is necessary to calculate the total energy of the light emitted in one hour = 3600s:

Furthermore, is necessary to find the  associated energy to the photon 0f 570nm with following formula:

h: Planck's constant = 6.62*10^-34 Js

c: speed of light = 3*10^8 m/s

wavelength = 570*10^-9 m

Finally you divide E' between Ep to find the number of photons:

the number of emitted photons is 4*10^22

thermal energy is the answer

energy can be converted from one form to another, but it cannot be created or destroyed in ordinary chemical or physical means. do not understand what you are asking but hope this