Answer:
78.35°
Explanation:
THIS IS THE COMPLETE QUESTION BELOW;
A layer of ethyl alcohol (n = 1.361) is on top of water (n = 1.333). To the nearest degree, at what angle relative to the normal to the interface of the two liquids is light totally reflected?
From Snell's Law,
(ni)/(nr) = Sin (θr) / Sin (θi)
Where
θi = Angle of Incidence
θr = Angle of refraction
ni = Refractive index given for ethyl alcohol
nr = Refractive index of medium from which light is refracted
ni = 1.361
nr = 1.333
, θr = 90° ( Critical Angle is reffered to as Angle of Incidence at refracted angle of 90°) (θi = θc)
(ni)/(nr) = Sin (θr) / Sin (θi)
1.361/ 1.333 = Sin (90°)/ Sin( θc)
1.021= 0.894/ Sin( θc)
Sin( θc)= (0.9794
θc = Sin⁻¹ 0.9794)
θc = 78.35°
Answer:
It looks like A is the correct answer.
its because it allows modern astronomers the ability to see farther out and more accuratly
I believe it’s 60km/h
I divided the total distance (120 km) by the time it took to get there (2h) to get this.
Answer:
Explanation:
Let the intensity of the noise be represented by I
Given that
40dB = 10 log 10 ( I /I•) ........ 1
I• is the lowest or threshold intensity of sound made.
I represents the intensity of the sound/ noise
The intensity of noise of 1000flies will be
β = 10 log 10 (1000I/I•)
Open up the bracket
β = 10 log 10(1000)+ 10 log 10(I/I•)
10 log 10(10^3)+10 log 10(I/I•)
3×10(10 log 10) +10 log 10(I/I•)
Recall, 10 log 10 = 1
30×1 + 10 log 10(I/I•).........2
Put equation 1 into 2
β =30+40
= 70db
