Answer:
- the coating’s index of refraction is 1.25
- the required thickness is 104.1667 nm
Explanation:
Given the data in the question;
Thickness of coating t = 100 nm
wavelength λ = 500nm
we know that refractive index is;
t = λ/4n
make n, the subject of formula
t4n = λ
n = λ / 4t
we substitute
n = 500 / ( 4 × 100 )
n = 500 / 400
n = 1.25
Therefore, the coating’s index of refraction is 1.25
2)
given that;
Index of refraction of the coating; n = 1.20
λ = 500 nm
thickness of coating t = ?
t = λ / 4n
we substitute
t = 500 / ( 4 × 1.2 )
t = 500 / 4.8
t = 104.1667 nm
Therefore, the required thickness is 104.1667 nm
Answer:
v<em>min</em> = 0.23 m/s
Explanation:
The golf ball must travel a distance equal to its diameter in the time between blade arrivals to avoid being hit. If there are 12 blades and 12 blade openings and they have the same width, then each blade or opening is 1/24 of a circle of is 2π/24 = 0.26 radians across.
Therefore, the time between the edge of one blade moving out of the way and the next blade moving in the way is
time = angular distance/angular velocity
⇒ t = 0.26 rad / 1.35 rad/s = 0.194 s
The golf ball must get completely through the blade path in this time, so must move a distance equal to its diameter in 0.194 s, therefore the speed of the golf ball is
v =d/t
⇒ v = 0.045 m / 0.194 s = 0.23 m/s
The magnetic field and force is weakest in the center of the magnet. The correct answer is C.
A wave with a large amplitude
a wave check
The answer is b, anything that has mass and takes up space