The primary purpose of a gear box is___________________?
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Answer: C. to obtain variable speeds
Explanation
The primary operational purpose of a gearbox in mechanical drive systems is to obtain variable speeds. By engaging different gear ratio combinations, a gearbox allows output shaft speed to change relative to input speed. This speed variability enables machinery to operate efficiently across a wide range of operational requirements. Gearboxes transmit rotational power between shafts using toothed wheels with proportional pitch diameters. Gear ratios determine the exact mechanical advantage, multiplying output torque while inversely reducing rotational speed. Mechanical power conservation dictates that speed reduction across a gearbox results in a corresponding torque increase.
Option A is secondary because torque production results directly from speed reduction ratios rather than being the primary goal. Option B describes only one direction of speed adjustment, whereas gearboxes provide multiple variable speed options. Options D and E are incorrect because gearboxes do not inherently increase system efficiency or dampen vibrations.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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