The meter installed in a vehicle that calculates and displays the total distance covered by the vehicle over time is commonly called what?

Introduction / Context:
Modern vehicles have several instruments on the dashboard to provide useful information to the driver. Two important ones are the speedometer and the odometer. The speedometer shows how fast the vehicle is moving at a given instant, while the odometer records the total distance traveled. The question asks you to identify the name of the meter that measures distance, which is a common point of confusion in basic general science and everyday knowledge.

Given Data / Assumptions:

• A vehicle is fitted with a meter to measure distance covered.
• The meter keeps a cumulative record over time, not just an instantaneous reading.
• Possible instruments mentioned include speedometer, odometer, thermometer, and a generic kilometre counter.
• We assume a typical car, bike, or similar road vehicle.

Concept / Approach:
The word odometer comes from Greek roots that mean way or path and measure. It is specifically designed to count how many kilometres or miles a vehicle has traveled during its lifetime. The reading usually appears as a rolling number display or a digital display on the dashboard. In contrast, the speedometer, as the name suggests, measures speed, which is distance per unit time, not total distance. A thermometer measures temperature and is unrelated to vehicle distance measurement. A so called kilometre counter is not the standard technical term, even though it describes the function informally. The correct scientific term used in vehicles is odometer.

Step-by-Step Solution:
Step 1: Identify that the quantity being measured is total distance covered by the vehicle.Step 2: Recall that in vehicles, speed is shown by the speedometer, while distance is shown by a different instrument.Step 3: Remember that the distance measuring device is called an odometer, often located within or near the speedometer dial.Step 4: Note that thermometer is used for temperature and does not relate to distance.Step 5: Conclude that the correct term for the meter that calculates distance covered is odometer.

Verification / Alternative check:
If you look at a vehicle dashboard, you will see a display labelled with total kilometres or miles, often called the odometer reading. Service schedules, resale valuations, and fuel efficiency calculations are all based on the odometer reading. The speedometer, on the other hand, has a moving needle or digital value that continuously changes as the speed varies. Since the question emphasises the meter that calculates distance covered, checking the dashboard terminology confirms that odometer is the appropriate word.

Why Other Options Are Wrong:
Speedometer measures the instantaneous speed of the vehicle in km per hour or miles per hour, not the cumulative distance, so option A is wrong. Thermometer measures temperature and has no direct link with distance measurement, so option C is clearly incorrect. Kilometre counter describes the function in everyday language but is not the standard scientific or technical term used in textbooks and exams, so option D is not preferred. Odometer is the correct technical name for this instrument.

Common Pitfalls:
Students often quickly choose speedometer because they associate it strongly with vehicle instruments. However, reading the phrase distance covered carefully should remind you that speed and distance are different physical quantities. Another pitfall is thinking that any term containing kilometre must be correct, but exams usually test recognition of standard terms like odometer. To avoid confusion, remember this pair: speedometer for speed and odometer for distance, both usually placed together on the vehicle dashboard.

Final Answer:
Odometer