It can also be called the thermal kinetic energy. The internal energy of a system is the total thermal kinetic energy and thermal potential energy of all its atoms and molecules. The Kinetic Theory of Matter is explains the kinetic energy of particles in an object.
The Pony Express
Chapter 1
At A Nation's Crisis
The Pony Express was the first rapid transit and the first fost mail line across the continent from the Missouri River to the Pacific Coast. It was a system
by means of which messages were carried swiftly on horseback across the plains and deserts, and over the mountains of the far West It brought the
Adontic coost and the Pacific slope ten days nearer to each other.
It had a brief existence of only sixteen months and was supplanted by the transcontinental telegraph. Yet it was of the greatest importance in
binding the East and West together at a time when overland travel was slow and cumbersome, and when a great national crisis made the rapid
communication of news between these sections an imperative necessity.
The Pony Express marked the highest development in overland travel prior to the coming of the Pacific railroad, which it preceded nine years.
It, in fact, proved the feasibility of a transcontinental road and demonstrated that such a line could be built and operated continuously the year
around-a feat that had always been regarded as impossible.
The operation of the Pony Express was a supreme achievement of physical endurance on the part of man and his ever faithful companion, the
horse. The history of this organization should be a lasting monument to the physical sacrifice of man and beast in an effort to accomplish
something worthwhile. Its history should be an enduring tribute to American courage and American organizing genius.
Read this line from the Pony Express excerpt
It hod a brief existence of only sixteen months and was supplanted by the transcontinental telegraph.
Based on the corres, what does the word "supplanted" mean? (5 points)
Defeated
Joined
Replaced
Os
Oo
Unearthed
I think the correct answer from the choices listed above is option A. Wave motion is a movement of energy through space or a medium . Some waves are visible light waves, heat waves, sound waves and the like. Hope this answers the question.
Answer:
his is a multi-part question. Once an answer is submitted, you will be unable to return to this part. Air enters a nozzle steadily at 2.21 kg/m3 and 40 m/s and leaves at 0.762 kg/m3 and 192 m/s. The inlet area of the nozzle is 90 cm2.
determine (a) the mass flow rate through the nozzle, and (b) the exit area of the nozzle.
a)0.7956kg/s
b)5.437 × 10⁻³m²
Explanation:
The concepts related to the change of mass flow for both entry and exit is applied
The general formula is defined by
![\dot{m}=\rho A V](https://tex.z-dn.net/?f=%5Cdot%7Bm%7D%3D%5Crho%20A%20V)
Where,
![\dot{m} = mass flow rate\\\rho = Density\\V = Velocity](https://tex.z-dn.net/?f=%5Cdot%7Bm%7D%20%3D%20mass%20flow%20rate%5C%5C%5Crho%20%3D%20Density%5C%5CV%20%3D%20Velocity)
values are divided by inlet(1) and outlet(2) by
![\rho_1 = 2.21kg/m^3V_1 = 40m/s](https://tex.z-dn.net/?f=%5Crho_1%20%3D%202.21kg%2Fm%5E3V_1%20%3D%2040m%2Fs)
![A_1 = 90*10^{-4}m^2\\\rho_2 = 0.762kg/m^3\\V_2 = 192m/s](https://tex.z-dn.net/?f=A_1%20%3D%2090%2A10%5E%7B-4%7Dm%5E2%5C%5C%5Crho_2%20%3D%200.762kg%2Fm%5E3%5C%5CV_2%20%3D%20192m%2Fs)
PART A) Applying the flow equation
![\dot{m} = \rho_1 A_1 V_1\\\dot{m} = (2.21)(90*10^{-4})(40)\\\dot{m} = 0.7956kg/s](https://tex.z-dn.net/?f=%5Cdot%7Bm%7D%20%3D%20%5Crho_1%20A_1%20V_1%5C%5C%5Cdot%7Bm%7D%20%3D%20%282.21%29%2890%2A10%5E%7B-4%7D%29%2840%29%5C%5C%5Cdot%7Bm%7D%20%3D%200.7956kg%2Fs)
PART B) For the exit area we need to arrange the equation in function of Area, that is
![A_2 = \frac{\dot{m}}{\rho_2 V_2}\\A_2 = \frac{0.7956}{(0.762)(192)}\\A_2 = 5.437*10^{-3}m^2](https://tex.z-dn.net/?f=A_2%20%3D%20%5Cfrac%7B%5Cdot%7Bm%7D%7D%7B%5Crho_2%20V_2%7D%5C%5CA_2%20%3D%20%5Cfrac%7B0.7956%7D%7B%280.762%29%28192%29%7D%5C%5CA_2%20%3D%205.437%2A10%5E%7B-3%7Dm%5E2)