Measurement of Length Distance

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What is Distance?

Two measures are there, such as distance and displacement, appear as the same, but both are dissimilar with altered meanings and explanations. The distance can be explained as the measurement of total space that an object has completed at a time during its motion.

  • Distance is reserved as a scalar quantity that depicts "how much space an object has traveled" in the course of its motion. 

  • Displacement is reserved as a vector quantity that mentions "the course of an object from its original to its final position"; it is the object's complete alteration in position.

Further, the displacement can be signified as the measurement of total space covered by an object along with its significant direction. We have concluded the vital modification between distance and displacement.

The distance is a mathematical measurement of how distant apart substances or places are. In our daily usage, distance can be referred to as a physical length or approximation built on other criteria (e.g., distance over two cities).

What is Distance in Physics?

Distance is the summation of the movement of a body without considering its direction. We can express distance as the total space, which is covered by an object despite its first or last point.

  • Distance and displacement are dissimilar measures, but they are interconnected. The distance should be equal to the displacement's magnitude.

  • Distance and displacement have the identical size only when we deliberate small intermissions. Meanwhile, the displacement is calculated along the straight (shortest) path between two points, and its value is always equal or lesser than the distance.

Several things can be meant about physical distance, such as:

  • Distance Traveled: The specific path's length is covered between two junctions, for example, the distance covered by walk while directing a maze.

  • Straight-Line Distance or Euclidean Distance: The length of the path in-between two points is the possible shortest path through space that could be considered if there were not any hurdles.

  • Geodesic distance: The length that falls between two points as the shortest path while enduring on some surface, for example, the distance of the great-circle along the curve of the Earth, the length of a precise path that comes back to the initial point. 

  • For example, a ball is thrown straight upward direction or the Earth when it completes one orbit.

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Let's visualize this diagram. Can you calculate the overall distance?

From the figure, the total distance covered by the boy will be:

D = (4 + 3 + 5) meter = 12 meters.

What is the Distance Between two Points?

Distance between any two points can be measured through the length. For instance, it has been concluded that the distance of a road is alternatively spoken how long the road is?

In the metric measurement system, the most shared units of distance are kilometers, meters, centimeters, and millimeters.

The alteration in this place can be calculated through the measurements of distance.

This permits us to distinguish how slowly, or fast motion is. There is a motion everywhere, such as the motion of a snail on the ground, a butterfly flying from flower to flower, and the flowing of the river in the obstacle-free paths. 

Besides, the flying of an airplane is high enough in the air, which makes jet trails, the moon rotating around the Earth, blood traveling inside our bodies, and many more.

The total distance covered = speed * total time taken.

Metric Units of Length Conversion Chart

Here you will find the unit of length conversion customary to metric units of lengths.

When the length is used in mathematics, we have an idea that 'Meter' is the standard unit of length, which is inscribed in short denoted by (m).

A metre length is separated into hundreds of equal parts, where a single part is centimetre symbolized as cm.

As such, 100 centimetre is 1 metre and 1 metre is 100 centimetre.

We know its use, such as kilometer is utilized for measurements of the long distances. We know that 1 kilometer equals 1000 meters. Here, the kilometer is written in short as km.

Metric Length Conversions


10 millimeters

1 cm

10 mm

1 decimeter

10 centimeters

1 dm

10 cm

1 meter

100 centimeters

1 m

100 cm

1 meter

10 decimeters

1 m

10 dm

1 kilometer

1000 meters

1 km

1000 m

Measurement of Length Distance

The distance can be exemplified as follows:

d = s * t


d = the distance traveled in metre

t = time taken to cover the distance in second

s = the speed in metre/sec

Generally, we use Kilometer as km, Meter as m, & Centimeter as cm as the length measurement units in our daily usage. These are the most used parameters for the measurement of distance.

FAQ (Frequently Asked Questions)

Q1. Two Bikes Start Driving from the Same Point, However, in Opposite Directions along North & South. Let the Distance is x. Find the Displacement of the Second Bike Moving Directing Southward?

Ans: Distance traveled = 'x' at a certain time.


+ x = displacement bike A at motion towards the North.

- x = displacement of bike B that moves in the southward direction.

As such, the answer is -x.

Q2. A Boy Moves Along the Straight Path of Side 10 m each in 30 Seconds. What will be the Total Time Taken by the boy to Cover up the Path?

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Ans: Let the initial point of the boy at point (A)

The distance travelled by the boy (A –B – C – D) = 4 * 10 = 40 m.

The total time is taken = 40 * 30 = 120 seconds.

Q3. An Object has Traveled by Some Distance. Does it have any Chance of Zero Displacements? Explain and Illustrate?

Ans: Yes, it has a chance of zero displacements. Zero displacements can be achieved only when both the starting and endpoint of the object is the same.

For illustration: Imagine a person is traveling along the circular path. His displacement will be zero if he returns to the same point where he started.

Q4. Can Distance Traveled by a Body in Motion be Negative?

Ans: Mathematically, the distance can be negative. Also, the total distance covered never decreases. Therefore, the negative and positive sign is used to indicate the magnitude of displacement as per the direction of the motion of the body.