Since energy cannot be created nor destroyed, the change in energy of the electron must be equal to the energy of the emitted photon.
The energy of the emitted photon is given by:

where
h is the Planck constant
f is the photon frequency
Substituting

, we find

This is the energy given to the emitted photon; it means this is also equal to the energy lost by the electron in the transition, so the variation of energy of the electron will have a negative sign (because the electron is losing energy by decaying from an excited state, with higher energy, to the ground state, with lower energy)
Answer : The average speed of the sprinter is, 34.95 Km/hr
Solution :
Average velocity : It is defined as the distance traveled by the time taken.
Formula used for average velocity :

where,
= average velocity
d = distance traveled = 200 m
t = time taken = 20.6 s
Now put all the given values in the above formula, we get the average velocity of the sprinter.

conversion :
(1 Km = 1000m)
(1 hr = 3600 s)
Therefore, the average speed of the sprinter is, 34.95 Km/hr
Answer:
Good question to ask in physics, sir maam
The question is a little confusing. An electromagnetic wave is radiation. One doesn’t emit the other. Take another look at the question and write it again please.
Answer:
The one in the middle
Explanation: i listened to the other person and i got it wrong, this is the answer for edge2020 sience review on energy!!!!
trust me its the middle one!!!!!
And everyone if ur not sure, like 100% sure about an answer dont answer at all cuz for 1: ur taking up a spot for others to answer. for 2: you could make people wrong. And for 3: its annoying. And 4: it makes stuff like this happen!
<u>NOT ARGUEING IM JUST PUTTING MY THOUGHTS AND OPINIONS OUT THERE ;)</u><em> many thanks.</em>