Answer:
3.066×10^21 photons/(s.m^2)
Explanation:
The power per area is:
Power/A = (# of photons /t /A)×(energy / photon)
E/photons = h×c/(λ)
photons /t /A = (Power/A)×λ /(h×c)
photons /t /A = (P/A)×λ/(hc)
photons /t /A = (680)×(678×10^-9)/(6.63×10^-34)×(3×10^-8)
= 3.066×10^21
Therefore, the number of photons per second per square meter 3.066×10^21 photons/(s.m^2).
it's because some versions have more steps and others have less
Answer: C
Explanation: As the universe stretches it expands more and more the distance between each other. Hope this helps.
Pressure = (total force) / (Area)
10,000 Pa = (1,000 N) / (Area)
Multiply each side by (Area) :
(10,000 Pa) x (Area) = 1,000 N
Divide each side by (10,000 Pa) :
Area = (1,000 N) / (10,000 Pa)
<em>Area = 0.1 m² </em>