normal force because it is perpendicular to the surface
Answer:
(a) 
(b) 
(c)
(d)
Solution:
As per the question:
Refractive index of medium 1, 
Angle of refraction for medium 1, 
Angle of refraction for medium 2, 
Now,
(a) The expression for the refractive index of medium 2 is given by using Snell's law:

where
= Refractive Index of medium 2
Now,

(b) The refractive index of medium 2 can be calculated by using the expression in part (a) as:


(c) To calculate the velocity of light in medium 1:
We know that:
Thus for medium 1
(d) To calculate the velocity of light in medium 2:
For medium 2:
Using the term c in this case is a little confusing. It is more generic to use a general velocity, v. That way, in this case, we know to use the speed of sound.
wavelength*frequency=v
wavelength_20Hz = (345 m/s)/(1/20s)
<span>wavelength_20kHz = (345 m/s)/(1/20000s)
I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!
</span>
I found: 16,905J
Explanation:
The Gravitational Potential Energy will depend on the work done against gravity (weight,
W=mg) to lift it at height h or:
U = mgh =750 * 9.8 *2.3 =16,905J
W = KE = 1/2m(v2f-v2i) also known as D just took the test