Introduction / Context:
In scientific and nautical contexts, the term “chronometer” refers to a highly accurate timekeeping instrument. Historically crucial for navigation at sea, marine chronometers allowed sailors to determine longitude by comparing local solar time with a reference time. Recognizing what a chronometer measures is a foundational general-science and general-knowledge skill tested in many competitive exams.
Given Data / Assumptions:
- Keyword: chronometer (from Greek “chronos” = time).
- Domain: measurement instruments.
- Goal: identify the physical quantity measured.
Concept / Approach:
Etymology is a powerful tool: “chrono-” indicates time. Instruments like thermometer (temperature), barometer (pressure), speedometer (speed) are named similarly. A chronometer is not just any clock; it denotes high-precision time measurement, traditionally exceeding the accuracy of ordinary watches, especially under environmental stress (temperature, motion). Therefore, among the options, “time” is the correct quantity measured.
Step-by-Step Solution:
1) Parse the stem: identify the instrument — chronometer.2) Apply morphology: chrono = time; meter = measure.3) Match to options: select “time.”4) Cross-check against historical usage (marine chronometers).
Verification / Alternative check:
Practical check: GPS-free navigation relied on a chronometer’s exact time to compute longitude differences. This usage confirms it measures time, not sound, color, or water waves.
Why Other Options Are Wrong:
colour contrast: Measured by colorimeters or spectrophotometers.sound waves: Measured in frequency/amplitude by oscilloscopes or sound level meters.water waves: Analyzed by wave gauges; unrelated to “chrono.”
Common Pitfalls:
Confusing the suffix “-meter” with any meter device without attending to the prefix. Always decode both parts to identify the quantity correctly.
Final Answer:
time
Discussion & Comments