At first glance, a roller coaster is something like a passenger train. It consists of a series of connected cars that move on tracks. But unlike a passenger train, a roller coaster has no engine or power source of its own. For most of the ride, the train is moved by gravity and momentum. To build up this momentum, you need to get the train to the top of the first hill or give it a powerful launch. The traditional lifting mechanism is a long length of chain running up the hill under the track. The chain is fastened in a loop, which is wound around a gear at the top of the hill and another one at the bottom of the hill. The gear at the bottom of the hill is turned by a simple motor. This turns the chain loop so that it continually moves up the hill like a long conveyer belt. The coaster cars grip onto the chain with several chain dogs, sturdy hinged hooks. When the train rolls to the bottom of the hill, the dogs catches onto the chain links. Once the chain dog is hooked, the chain simply pulls the train to the top of the hill. At the summit, the chain dog is released and the train starts its descent down the hill.
AI explanationShows the answer. Tap to open.
Question Focus: The diagram label points to the long moving part that pulls the train up the hill.
Correct Answer: G
Why this is correct: The diagram shows the long moving part under the track. The passage clearly says the lifting mechanism is a long length of chain that moves up the hill. So the answer is chain.
Passage Reference: The traditional lifting mechanism is a long length of chain running up the hill under the track. The chain is fastened in a loop, which is wound around a gear at the top of the hill and another one at the bottom of the hill. The gear at the bottom of the hill is turned by a simple motor. This turns the chain loop so that it continually moves up the hill like a long conveyer belt.
Common Mistake: Many students choose belt because the passage says "like a long conveyer belt". But that is only a comparison, not the real name. This is a paraphrase trap.
Paraphrasing: Passage: 'long length of chain running up the hill' = Diagram: 'moving lifting part'
Tips: When the passage says "like" or "as", look for the real object name, not the comparison.
Key Vocabulary:
- mechanism = machine part
- conveyer belt = moving belt
Question Focus: The diagram label points to the shape formed by the chain around the top and bottom.
Correct Answer: F
Passage Reference: The chain is fastened in a loop, which is wound around a gear at the top of the hill and another one at the bottom of the hill.
Why this is correct: The diagram shows the chain going around and coming back again. The passage says the chain is fastened in a loop, which matches this shape exactly. So the answer is loop.
Common Mistake: Some students choose gear because the loop goes around gears. But the label asks for the shape of the chain, not the wheel it wraps around. This is a context shift trap.
Paraphrasing: Passage: 'fastened in a loop' = Diagram: 'chain shape'
Tips: Check if the label wants a shape, a movement, or a machine part. Do not mix them.
Key Vocabulary:
- fastened = fixed
- wound around = wrapped around
Question Focus: The diagram label points to the round wheel at the top or bottom that the chain wraps around.
Correct Answer: B
Passage Reference: which is wound around a gear at the top of the hill and another one at the bottom of the hill.
Why this is correct: The diagram shows a wheel that the chain goes around. The passage clearly names this part as a gear. So the answer is gear.
Common Mistake: Students sometimes choose motor, but the motor turns the gear. It is not the wheel itself. This is a cause vs object confusion, a type of context shift trap.
Paraphrasing: Passage: 'wound around a gear' = Diagram: 'round wheel'
Tips: If two parts work together, ask which one you can actually see in the diagram.
Key Vocabulary:
- gear = toothed wheel
- wound = wrapped
Question Focus: The diagram label points to the power source that turns the gear.
Correct Answer: C
Passage Reference: The gear at the bottom of the hill is turned by a simple motor. This turns the chain loop so that it continually moves up the hill like a long conveyer belt. The coaster cars grip onto the chain with
Why this is correct: The diagram shows the device connected to the gear that makes it move. The passage says the gear is turned by a simple motor. So the answer is motor.
Common Mistake: Some students choose engine, but the passage clearly says the roller coaster has no engine. This is a contradiction trap.
Paraphrasing: Passage: 'turned by a simple motor' = Diagram: 'power source'
Tips: If the passage says something does NOT exist, never choose it from the options.
Key Vocabulary:
- motor = machine that makes things move
- turn = rotate
General Tips:
- Diagram labels usually follow the same order as the passage. Read from top to bottom.
- Always match the exact meaning, not a comparison or example.
- If two options seem similar, ask what the diagram label is really pointing to.
- Cross out each option after you use it to avoid repeating mistakes.
The rest of this explanation is for members. Sign in free to read why the other options are wrong, key words and tips.
Sign in to read the full explanation