Answer:
a) - 72.5°c
b) pressure = 3625.13 Pa
c) density = 0.063 kg/m^3
d) it is a subsonic aircraft
Explanation:
a) Determine Temperature
Temperature at 19.5 km ( 19500 m )
T = -131 + ( 0.003 * altitude in meters )
= -131 + ( 0.003 * 19500 ) = - 72.5°c
b) Determine pressure and density at 19.5 km altitude
Given :
Po (atmospheric pressure at sea level ) = 101kpa
R ( gas constant of air ) = 0.287 KJ/Kgk
T = -72.5°c ≈ 200.5 k
pressure = 3625.13 Pa
hence density = 0.063 kg/m^3
attached below is the remaining part of the solution
C) determine if the aircraft is subsonic or super sonic
Velocity ( v ) = 
= 
= 283.8 m/s
hence it is a subsonic aircraft
Answer:
the correct answer is A
Explanation:
In an Einstein-type analysis, the photon is absorbed, it loses all its energy, therefore the electron must receive all or none of the energy of the incident photon. In a type of inelastic shock.
Let's analyze the different answers
A) true. In photon it is completely absorbed or passes without interaction
B) False. The photon must change energy, but in this case there is no absorption of the photon
C) False. In the insistent analyzes, the quantization of the electron in discrete states is not mentioned.
Therefore the correct answer is A
Answer:
The first part can be solved via conservation of energy.
For the second part,
the free body diagram of the car should be as follows:
- weight in the downwards direction
- normal force of the track to the car in the downwards direction
The total force should be equal to the centripetal force by Newton's Second Law.
where 
because we are looking for the case where the car loses contact.
Now we know the minimum velocity that the car should have. Using the energy conservation found in the first part, we can calculate the minimum height.
Explanation:
The point that might confuse you in this question is the direction of the normal force at the top of the loop.
We usually use the normal force opposite to the weight. However, normal force is the force that the road exerts on us. Imagine that the car goes through the loop very very fast. Its tires will feel a great amount of normal force, if its velocity is quite high. By the same logic, if its velocity is too low, it might not feel a normal force at all, which means losing contact with the track.
The inner planets are not colder or larger than the outer ones,
and they're not comprised of gas.
The inner planets are the ones that are made of rock. ( D ).
Question 18: a
question 19: b
question 20: c
