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:
Change in mechanical energy, 
Explanation:
It is given that,
Mass of the projectile, m = 12 kg
Speed of the projectile, v = 20 m/s
Maximum height, h = 18 m
Initially, the projectile have only kinetic energy. it is given by :


K = 2400 J
Finally, it have only potential energy. it is given by :
P = mgh

P =2116.8 J
The change in mechanical energy is given by :



So, the change in mechanical energy is 283.2 J. Hence, this is the required solution.
Option C is the correct answer
Answer: P = FV becuase all of them are equal in strength.
Explanation: In the straight forward cases where a constant force moves an object at constant velocity, the power is just P = Fv. In a more general case where the velocity is not in the same direction as the force, then the scalar product offorce and velocity must be used. P = Power, F = Force, V = Velocity.
Hoped This Helped!
Based on the calculations, the speed required for this satellite to stay in orbit is equal to 1.8 × 10³ m/s.
<u>Given the following data:</u>
- Gravitational constant = 6.67 × 10⁻¹¹ m/kg²
- Mass of Moon = 7.36 × 10²² kg
- Distance, r = 4.2 × 10⁶ m.
<h3>How to determine the speed of this satellite?</h3>
In order to determine the speed of this satellite to stay in orbit, the centripetal force acting on it must be sufficient to change its direction.
This ultimately implies that, the centripetal force must be equal to the gravitational force as shown below:
Fc = Fg
mv²/r = GmM/r²
<u>Where:</u>
- m is the mass of the satellite.
Making v the subject of formula, we have;
v = √(GM/r)
Substituting the given parameters into the formula, we have;
v = √(6.67 × 10⁻¹¹ × 7.36 × 10²²/4.2 × 10⁶)
v = √(1,168,838.095)
v = 1,081.13 m/s.
Speed, v = 1.8 × 10³ m/s.
Read more on speed here: brainly.com/question/20162935
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