An 11.8 eV photon is absorbed by an electron in an atom, causing the electron to be excited from level 1 to level 3. The electron then emits a 4.1 eV photon and shifts to level 2. What photon will be emitted when the electron moves back to level 1

Explanation:

energy absorbed by electron to get excited from level 1 to level 3

= 11.8 eV

energy released by electron when it  goes from level 3 to level 2 = 4.1 eV

energy released when electron goes from level 2 to level 1 = 11.8 - 4.1 = 7.7 eV

photon emitted = 7.7 eV photon .

note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol  

b. a hockey puck sliding across the ice  

c. a compressed spring  

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice   is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice   is the correct option.