1. The problem statement, all variables and given/known data That is what I learnt, and that it is expressed in newton*meter. Then I learnt that G is equal to 6.47 x 10^ -11 joules and that h is equal to 6.6262 x 10^ -34 joules x sec (N*m*s)and that one photon of light (say red) is equal to 4x 10^ 14 Hz(frequency) and its energy is E (light) = h * f, so it has energy= 4x 10^ 14 h (N*m*s) If these data are correct, can you explain to me 1) what kind of energy is the energy of light[/I] , what is it called, is it just Kynetic Energy (* sec)? or has it got its own definition? edit "should I call it just energy of light"? in EMR ( R stands for , not energy) "is it electromagnetic energy? (hope it is clear now what I am asking for) 2) how do you relate h to KE? A photon has E= Joules* sec an electron ( in motion has KE = 4x 10^14) Joules . why its energy is not Joules*sec, hasn't it got the same energy of a red-ray photon? the same energy every sec? they both run every second and indefinitely! what is the difference between the two energies? (when a ray meets an electron in Compton scattering its energy is transformed in the sane amount of KE, so what is the difference? Likewise an electron dropping from an orbit changes its KE into light how do you account for the chance of unit?) 3)and how do you relate h to G? is h (Nms)= G(Nm)* sec? 3. The attempt at a solution ?