Displacement Formula Physics

Displacement is the distance between two different positions of an object in m motion. So, it depends on the initial position and its final position. Also, displacement is the minimum distance between the starting and final positions. In this article, we will see its concept and displacement formula physics. Some examples are also given here. Let us learn the interesting concept!

                                                                                                                                           Source: en.wikipedia.org

Displacement Formula Physics

How is Displacement defined?

As this is a calculation that measures distance, its standard unit is the meter (m). For many applications in Physics concept of displacement is very useful.  Displacement is the difference between two positions of an object. It is a vector quantity because it has a direction and magnitude as well. It is represented as an arrow that points from the starting position to the last position.

For Example, if an object moves from the first position to the last position, then the object’s position changes. This change in the position of an object is referred to as displacement.

The Formula of Displacement

The official displacement formula is as follows:

\(s = s_f – s_i\)

Where,

s	displacement
\(s_i\)	initial position
\(s_f\)	final position

Displacements are not necessarily always positive. It can be zero or negative as well. If the positive direction is to the right of the origin, then a negative displacement means that the object has moved towards the left of the origin.

In Physics problems, we can choose to place the origin of our position-measuring system wherever is convenient. The measurement of the position of an object depends on where we choose to place the origin.

The displacement from an initial position s_i to a final position s_f does not depend on the position of the origin. This is because the displacement depends only on the difference between the two positions, and not the positions themselves.

Distance and displacement are two quantities that are similar. But these are having some differences also.

• Distance is a scalar quantity that refers to how much ground an object has covered during the motion.
• Displacement is a vector quantity which refers to how far out of place an object is, it is the object’s overall change in the position.

Solved Examples

Q.1: What will be the displacement of a relay race team if they begin at the school, run 16 km and finish back at the school?

Solution: The displacement of the runners will be 0 km. While they have covered a distance of 16 km miles, they are not displaced at all. They finish from where they have started. Therefore, round-trip motions always have a displacement of zero.

Q.2:  A man travels 250 km to North but then back-tracks to South for 105 km, to pick up a friend. What is his total displacement?

Answer: Starting position,

\(s_i\) = 0.

His final position \(s_f\)  is the distance traveled North minus the distance traveled South.

Calculating displacement,

\(s = s_f – s_i\)

d = (250 km in North – 105 km in south) – 0

d = 145 km towards North.

Therefore the displacement will be 145 km towards North.