A handheld red laser pointer is rated to deliver an optical output power of at a…
PHYSICS · Multi-part · CBSE · Physics · Dual Nature of Radiation and Matter · Dual Nature of Radiation and Matter
Problem
A handheld red laser pointer is rated to deliver an optical output power of 5.0mW at a wavelength of 650nm.
During a brief press of the on-button, the laser remains continuously on for exactly 601s (the duration of one video frame at 60 fps).
(a) Calculate the energy carried by a single photon emitted by the laser.
(b) Determine the number of photons the laser emits each second while it is operating at the rated power.
(c) Find the total number of photons emitted during the 601s burst.
(d) Suppose the laser beam passes through a window that transmits only 88% of the incident light at this wavelength. Recalculate the number of photons that emerge from the window during the same burst.