Force and Motion: Distance and Displacement

Distance and Displacement

• Three paths (1, 2, and 3) can be taken to go to school from Seema's house, but only path 1 has a fixed direction due east on a straight path.
• Paths 2 and 3 do not have a fixed direction, showing the distance between the house and the school.
• Path 1 is the shortest path and represents the displacement between the house and the school.
• Distance is the length of the path traveled by a body in any direction, measured in meters (m) in the SI system.
• Displacement is the shortest distance between two points, also measured in meters (m) in the SI system.
• Distance and displacement are equal only when the motion of a body is fully along a straight path.
• In other cases, distance and displacement are not equal.

Distance and Displacement

• Distance is the total length covered while moving from one place to another in any direction.
• It is represented by a magnitude without considering its direction.
• The SI unit of distance is metre (m).
• Distance = Speed × Time (d = v × t)

Displacement

• Displacement is the shortest distance covered by a moving body in a particular direction.
• It is a vector quantity as it has its magnitude and direction.
• A vector is represented by a line with an arrow, where the arrow represents the direction of the vector and the length of the line represents magnitude.
• Displacement has both magnitude and direction, whereas distance only has magnitude.
• Example: a displacement of 16m due east is represented by a straight-line AB with an arrow pointing east.

Difference between Distance and Displacement

• Distance and displacement are not the same concepts.
• Distance does not have a direction, whereas displacement has a specific direction.
• The shortest distance between two points is called displacement.