physics question

Question

Two photons are both travelling through empty space. One has a wavelength of 500 nm and the

other has a wavelength of 1000 nm. Which of the following is true? Select all that apply. 

A.  The 500 nm photon has a higher frequency than the 1000 nm photons

B. The 1000 nm photon carries more energy than the 500 nm photon.

C. The 500 nm photon travels faster than the 1000 nm photon.

D.  The 1000 nm photon has a higher temperature than the 500 nm photon.

Answer 1

The photon with shorter wavelength has a higher frequency and carries more energy. In a vacuum, all photons travel at the same speed, which is the speed of light. Photons do not have temperature. (Temperature is associated with the motion of microscopic particles with mass. Photons are "massless.") From these facts you can conclude that only (A) is correct.