The complex of full-size helicopters gets less efficient when shrunk, that standard mini helicopters expend most of their power simply fighting to stay stable in the air. The researchers realised that a simpler aircraft designed to stay stable passively would use much less power and reduce manufacturing costs to boot.
It turns out that nature them to it. The seeds of trees such as the maple have a single-blade structure that them to fly far away and drift safely to the ground. These seeds, known as samaras, need no engine to through the air, thanks to a process called autorotation. By analysing the behaviour of the samara with high-speed cameras, Ulrich and his team were able to copy its design.
The samara copter is not the first single-winged helicopter – one was flown in 1952, and others have been attempted since – but it is the first to take advantage of the samara’s autorotation. This allows Ulrich’s vehicle to perform some neat tricks, such as falling safely to the ground if its motor fails or using vertical columns of air to stay aloft indefinitely. “We can turn off the motor and autorotate, which requires no power to sustain,” says Ulrich.
Result:
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Correct answer: design
Explanation: The word 'design' fits grammatically as a noun that refers to the arrangement or plan of the helicopter's structure. It aligns contextually with the discussion of how full-size helicopters operate and how their efficiency changes when scaled down, making it the most appropriate choice.
Meaning: 'Design' refers to the way something is planned or created, particularly in terms of its structure and functionality.
Wrong options:
- performance: While 'performance' relates to how well something functions, it does not specifically address the structural aspect being discussed here.
- usage: 'Usage' refers to how something is used, which is not the focus of the sentence regarding the efficiency of helicopter design.
- mileage: 'Mileage' typically refers to distance traveled per unit of fuel and is irrelevant in this context.
Correct answer: meaning
Explanation: The word 'meaning' serves as a noun that indicates the significance or implication of the preceding statement about mini helicopters. It fits grammatically and contextually, as it introduces the consequence of the design inefficiencies discussed.
Meaning: 'Meaning' refers to the significance or interpretation of something, in this case, the implications of the design issues with mini helicopters.
Wrong options:
- insinuating: 'Insinuating' is a verb that suggests something indirectly, which does not fit the grammatical structure needed here.
- clearing: 'Clearing' is a verb that does not logically connect to the context of explaining the implications of helicopter design.
- inspiring: 'Inspiring' is an adjective that does not fit grammatically as it does not serve as a noun to convey the intended meaning.
Correct answer: had beaten
Explanation: The phrase 'had beaten' is in the past perfect tense, indicating an action that was completed before another past action. This fits grammatically and contextually, as it suggests that nature had already achieved stability before the researchers' realization.
Meaning: 'Had beaten' means that nature had already surpassed or outperformed the researchers in terms of design efficiency.
Wrong options:
- beating: 'Beating' is in the present continuous tense, which does not fit the past context of the sentence.
- had beats: 'Had beats' is grammatically incorrect as 'beats' is not in the correct form for past perfect tense.
- was beating: 'Was beating' is in the past continuous tense, which does not convey the completed action needed in this context.
Correct answer: allows
Explanation: The word 'allows' is a verb that indicates permission or capability, fitting grammatically and contextually as it describes the function of the seed's structure in enabling flight.
Meaning: 'Allows' means to make it possible for something to happen, in this case, enabling the seeds to fly away.
Wrong options:
- disrupts: 'Disrupts' implies causing disorder, which contradicts the intended meaning of facilitating flight.
- prevents: 'Prevents' suggests stopping something from happening, which is the opposite of what is intended in this context.
- scatters: 'Scatters' implies spreading out, which does not accurately describe the function of the seed's structure in aiding flight.
Correct answer: spin
Explanation: The word 'spin' is a verb that describes the action of rotating, which fits grammatically and contextually as it refers to how the samara moves through the air without an engine.
Meaning: 'Spin' means to rotate rapidly around an axis, which is how the samara travels through the air.
Wrong options:
- soar: 'Soar' implies flying high and gracefully, which does not accurately describe the action of the samara's movement in this context.
- sway: 'Sway' suggests a side-to-side motion, which does not fit the description of the samara's flight mechanism.
- swing: 'Swing' implies a pendulum-like motion, which is not applicable to the way samaras move through the air.
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