I believe the correct response would be true, thermal energy or heat that is produced by friction usually cannot be used to do work.
Answer:
The reflected angle is 20 °.
The angle of refraction = 12.34°.
Explanation:
For reflection,
Angle of incidence = Angle of the reflection.
Thus,
Given that the angle of incidence is 20 °
So, the reflected angle is 20°.
For refraction,
Using Snell's law as:

Where,
Θ₁ is the angle of incidence
Θ₂ is the angle of refraction
n₁ is the refractive index of water which is 1
n₂ is the refractive index of water which is 1.6
So,


Angle of refraction = sin⁻¹ 0.56 = 12.34°.
I don’t understand what are you trying to do ?
Answer:
The apparent weight is 5 times greater than the original weight at the bottom.
Explanation:
Given:
Mass of the pilot, m = 84 kg
Velocity of the jet, v = 345 m/s
Radius of the loop, R = 3.033 km = 3.033 * 10^3 m
We have to find the apparent weight that the pilot feels.
Let the apparent weight be "N" .
Apparent weight :
- It is based on where is the position of the pilot in the loop-the-loop.
- The apparent weight is the highest at the bottom of the loop-the-loop.
- Because the weight acts down and the normal force acts towards the center of the circle.
From the FBD shown we can say that :
apparent weight (N)
⇒ 
⇒ 
⇒ 
⇒ 
Therefore,
The force exerted by the seat on the pilot at the bottom of the loop is greater than the pilots weight by a factor of 5.