Fermi
·
Concept Library
·
Courses
·
Books
·
Problems
·
Simulations
·
Math Wiki
·
High School
Fermi
›
Problems
Physics
Physics
Problem
Suppose
3.1
×
10
−
18
3.1 \times 10^{-18}
3.1
×
1
0
−
18
J energy is needed by the interior of the human eye to see an object. How many photon of light of
λ
=
400
\lambda = 400
λ
=
400
nm will be needed to see the object? (
h
=
6.6
×
10
−
34
h = 6.6 \times 10^{-34}
h
=
6.6
×
1
0
−
34
Js)
Browse the problem library