Read the given passage and answer the questions that follow. Key factors influencing subway air pollution will include station depth, date of construction, type of ventilation (natural/air conditioning), types of brakes (electromagnetic or conventional brake pads) and wheels (rubber or steel) used on the trains, train frequency and more recently the presence or absence of platform screen-door systems. In particular, much subway particulate matter is sourced from moving train parts such as wheels and brake pads, as well as from the steel rails and power-supply materials, making the particles dominantly iron-containing. To date, there is no clear epidemiological indication of abnormal health effects on underground workers and commuters. New York subway workers have been exposed to such air without significant observed impacts on their health, and no increased risk of lung cancer was found among subway train drivers in the Stockholm subway system. But a note of caution is struck by the observations of scholars who found that employees working on the platforms of Stockholm underground, where PM concentrations were greatest, tended to have higher levels of risk markers for cardiovascular disease than ticket sellers and train drivers. The dominantly ferrous particles are mixed with particles from a range of other sources ,including rock ballast from the track, biological aerosols such as bacteria and viruses, and air from the outdoors, and driven through the tunnel system on turbulent air currents generated by the trains themselves and ventilation systems.
Select the most suitable word from the passage which means ‘not covered or hidden’.
Exposed
Understanding Vocabulary in the Subway Air Pollution Passage
The question asks us to identify a word from the given passage that means ‘not covered or hidden’. To answer this, we need to read the passage carefully and understand the context in which different words are used. We will then look at the provided options and see which word best fits the definition ‘not covered or hidden’ based on its usage in the text.
Analyzing the Passage and Options for Word Meaning
The passage discusses factors influencing subway air pollution, the source of particles, and potential health effects on workers and commuters. Let's examine the options provided and their meanings in the context of the passage:
- Turbulent: The passage mentions “turbulent air currents generated by the trains themselves and ventilation systems.” Here, ‘turbulent’ describes the nature of the air currents – being irregular, disordered, or agitated. This does not mean ‘not covered or hidden’.
- Sourced: The passage states that “much subway particulate matter is sourced from moving train parts…” Here, ‘sourced’ means originated or obtained from. This refers to the origin of the particles, not whether something is covered or hidden.
- Exposed: The passage says, “New York subway workers have been exposed to such air without significant observed impacts on their health…” In this sentence, ‘exposed’ means being subjected to or brought into contact with the subway air. If someone is ‘exposed’ to air, they are in the open air, not covered or hidden from it. This aligns well with the definition ‘not covered or hidden’.
- Abnormal: The passage states, “…there is no clear epidemiological indication of abnormal health effects on underground workers and commuters.” Here, ‘abnormal’ means deviating from what is normal or usual. This describes a type of health effect, not whether something is covered or hidden.
Identifying the Correct Word from the Text
Based on the analysis of the options and their usage in the passage, the word ‘exposed’ is the most suitable word that means ‘not covered or hidden’. When the passage states that workers were ‘exposed’ to air, it implies they were in a situation where they were in direct contact with the air, not shielded or hidden from it.
Therefore, the word from the passage that means ‘not covered or hidden’ is ‘Exposed’.
Revision Table: Key Vocabulary
| Word from Passage | Context in Passage | Meaning in Context | Does it mean ‘not covered or hidden’? |
|---|---|---|---|
| Turbulent | Turbulent air currents | Irregular, disordered movement | No |
| Sourced | Particles sourced from parts | Originated from, obtained from | No |
| Exposed | Workers exposed to air | Subjected to, in contact with, not shielded | Yes |
| Abnormal | Abnormal health effects | Deviating from normal | No |
Additional Information: Understanding Word Meanings
Understanding the meaning of words within a specific context is a crucial skill in reading comprehension. Words can sometimes have multiple meanings, so it's important to look at how the word is used in the sentence and the overall theme of the passage.
For instance, the word ‘exposed’ can also mean 'revealed' or 'made known', but in the context of being ‘exposed to air’ or ‘exposed to sunlight’, it clearly refers to being in a state where something is not covered or protected from the environment.
When encountering an unfamiliar word, consider the surrounding words and sentences, look for clues in the sentence structure, and if possible, think of synonyms or antonyms that might fit the context. Comparing the word's usage to its definition helps confirm understanding.
Important Questions from Miscellaneous
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A railway wagon (open at the top) of mass M1 is moving with speed v1 along a straight track. As a result of rain, after some time it gets partially filled with water so that the mass of the wagon becomes M2 and speed becomes v2. Taking the rain to be falling vertically and the water stationery inside the wagon, the relation between the two speeds v1 and v2 is :
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1. Distance between the longitudes becomes zero on North Pole and South Pole.
2. Distance between the longitudes is maximum on the Equator.
3. Number of longitudes is more than number of latitudes.
Which of the statements given above is/are correct?
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