Is Distance Expressed More by 'Time' Than 'Length'? [Reading Science]

What is the distance between Seoul and Busan?
Photo by Google Maps Capture

[Asia Economy Reporter Kim Jong-hwa] When indicating distance in daily life, we use 'meter (m)' or 'kilometer (km)'. However, in actual conversations, time is used more often than these units. Why is that? Is it because m or km are inconvenient?

This is part of a typical conversation with a coworker. It includes 'distance', but if you distinguish between everyday casual talk and conversations trying to convey exact distances, it would go something like this.

"How long does it take from home to the subway? (How far is it from home to the subway?)"

"About 5 minutes on foot (the distance from the front door of the house to the subway entrance is about 600m)."

"How long does it take to get to work? (How far is it from home to the office?)"

"30 minutes by subway, 10 minutes to the subway? (The distance from the front door of the house to the subway entrance is about 1.2 km, and since it takes about 2 minutes to pass one subway station, you pass 15 stations. Considering the subway's average speed is 50~60 km/h, the distance between stations can be estimated at about 1.5~2 km. It takes 5 minutes from the subway exit to the office, about 600m, so the total distance to the office is roughly 24~32 km.)

How does that sound? Saying '5 minutes on foot' or '30 minutes by subway' is simple, but expressing it precisely in terms of distance becomes complicated and the concept of distance becomes unclear.

Therefore, in daily life, we use shortened expressions like '5 minutes from home to the subway' or '1 hour to get to work'. In other words, expressing distance in terms of time is easier to understand. Scientifically, distance is a value obtained by multiplying speed and time.

The formula 'Distance = Speed x Time' holds true. So, expressing distance in terms of time is easier and quicker to understand than using units like m or km.

Even if you ask precisely and answer precisely, if someone asks "How far is your commute?" and the reply is "It's 1.2 km from the front door to the subway entrance, 24.6 km by subway, and 600m from the subway exit to the office. So, a total of 26.4 km," wouldn't that be frustrating for both parties?

For example, if you were to talk about the Earth's circumference, which is about 40,000 km, how should you express it so the other person can understand well?

If you drive a car at 100 km/h, it takes 400 hours. Assuming you drive 10 hours a day only on highways, it would take 40 days to go around the Earth once. Instead of simply saying "40,000 km," expressing it as "You have to drive for 40 days by car" or "You need to drive 10 hours a day for 40 days at 100 km/h" would be easier to understand.

Distances are easier to understand when expressed in terms of time. Vehicles driving on the Gyeongbu Expressway.
[Photo by YouTube screen capture]

This is the kind of expression commonly used in the media. Adding the speed of the means of transportation helps readers understand more easily. A common expression is "500 km from Seoul to Busan."

Usually, people say "It's a 5-hour drive from Seoul to Busan," and when describing holiday traffic jams, they say "It usually takes 5 hours by car from Seoul to Busan, but now it takes about 8 hours." Expressing distance in terms of time is easier to understand.