Directions: In the following passage, certain words and phrases are underlined and numbered. The questions will provide alternatives for the underlined portion. You should choose the alternative that best expresses the idea in standard written English and is worded most consistently with the tone of the passage. If you believe the original version is best, then choose “NO CHANGE.” There will also be questions about sections of the passage or about the passage as a whole. Read the entire passage before answering any of the questions. For some questions you may need to read beyond the underlined section in order to determine the correct answer.
The Speed of Sound
The term “supersonic” refers to anything that travels faster than the speed of sound. When the last of the supersonic Concorde passenger planes made its final trip across the Atlantic in November of 2003, an interesting (1) chapter in history was finally closed. The fleet of supersonic Concorde SSTs, or “Supersonic Transports,” which were jointly operated by Air France and British Airways, has been making the Intercontinental trip across the Atlantic for almost thirty years. These amazing machines cruised at Mach 2 which is (2) more than twice the speed of sound. They flew to a height (3) almost twice that of standard passenger airplanes. The Concorde routinely made the trip from New York to London in less than three hours and was much more expensive than normal transatlantic flights. Though the majority of the passengers who traveled on the Concorde were celebrities or the extremely wealthy, it also attracted ordinary people who simply wanted to know how it felt to travel faster than the speed of sound. Some of these, (4) would save money for years just to gain that knowledge.
What is the speed of sound? Many people are surprised to learn that there is no fixed answer to this question. The speed that (5) sound travels through a given medium depends on a number of factors. So that we may better begin to understand (6) the speed of sound, we must first understand what a “sound” really is.
The standard dictionary definition of sound is “a vibration or disturbance transmitted, like waves through water, through a material medium such as a gas.” Our ears are able to pick up those sound waves and convert (7) them into what we hear. This means that the speed at which sound travels through gas directly depends on what gas it is traveling through, and the temperature and pressure of the gas. (8) When discussing aircraft breaking the speed of sound, that gas medium, of course, is air. As air temperature and pressure decrease with altitude (9), so does the speed of sound. An airplane flying at the speed of sound at sea level is traveling roughly at 761 mph; however (10) when that same plane climbs to 20,000 feet, the speed of sound is only about 707 mph. This is why the Concorde’s cruising altitude was so much higher than that of a regular passenger aircraft; planes can reach supersonic speeds more easily at higher altitudes. (11)
In the years since the Concorde has been (12) decommissioned, only fighter pilots and astronauts have been able to experience the sensation of breaking “the sound barrier.” But that is all about to change very soon. (13) Newer and faster supersonic passenger planes are being developed that will be technologically superior to the Concorde and much cheaper to operate. That means we can expect that in the very near future, (14) supersonic passenger travel will be available not only to the rich and famous, but also be for (15) the masses, so they, too, can experience life at speeds faster than the speed of sound.
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November, of 2003 an interesting
November of 2003 an interesting
November of 2003; an interesting
Mach 2, which
a speed of Mach 2, which is
at an altitude
toward an altitude
Among these were those who
In order that we may understand
depends directly on the type, temperature, and pressure of the gas it is traveling through.
directly depends on what gas it is, and also on the temperature and pressure of that gas.
depends directly on the type, temperature, and pressure of the gas.
with a drop in altitude
at higher altitudes
they’re much faster.
they use much more fuel than regular aircraft.
they’re rarely visible because they fly above the cloud cover.
came to be
Soon, however, that is about to change.
Soon, however, that will change.
That is about to change soon.
So then, in the near future
We can expect, then, that in the near future
but also be available to
but also to
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