Answer: 4m
Explanation:
Since the angle of incidence of a plane mirror can be anything from 0 to 90°
Assuming that the place is a perfectly square 4×4m room
The incident ray would be 45° for the choir(object) at a 4m distance, this is still within the range of values.
We do not forget also, that the focal length of a plane mirror is infinity, the organist would in fact see farther than 4m if need be. And wider
Answer:
λ = 451.7 nm
Explanation:
The expression for the constructive interference of the double diffraction experiment is
d sin θ = m λ
let's use trigonometry
tan θ = y / L
how the experiment occurs at very small angles
tan θ = sin θ / cos θ = sin θ
sin θ = y / L
we substitute
d y / L = m λ
λ =
let's calculate
λ =
λ = 4.51699 10⁻⁷ m
λ = 4.517 10⁻⁷ m (109 nm / 1m)
λ = 451.7 nm
D, it is considered unethical today
Displacement = 31 - 16 = +15 m