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# How to find displacement in physics

In this article learn about how to find displacement in physics. Here we will learn about Displacement formulas and how to use them to find displacement in physics.

Many people use the terms distance and displacement interchangeably. But in reality, both distance and displacement are two different concepts.

Displacement is defined as a change in the position of an object. Now when an object is displaced it covers a distance in a particular direction.

Since it has both magnitude and direction displacement is a vector quantity. For more clarity consider an object moving from point A to point B.

Here the object under consideration moves through this red line path. Here this red line’s path gives the total distance covered by the object moving from point A to point B.

But the green line points from point A to point B in the shortest possible distance between these two points with its direction pointing from initial point A to final point B. This shortest distance from point A to point B is nothing but a displacement of the object.

Now as such we have two cases of formulas for finding displacement in kinematics.

• The first one is where only the position of the object is given that is we have information about the initial and final positions of the object in motion.
• In our second case, we use kinematics equations that involve distance along with other parameters like velocity, acceleration, and time.

However, in this article, we would only find the displacement of the object without involving other kinematics quantities like velocity, acceleration, and time. So, here we will learn how to find displacement without time.

Let us now look at how to find displacement in physics.

## The formula for displacement in physics

If we have knowledge about the initial and final position of the object then displacement of the object is given by the formula

$\Delta x=x_f-x_i$

where,
$x_f$ is the final position
$x_i$ is the initial position
$\Delta x$ is a change in the position of the object

Now this formula gives the displacement of the object moving in a straight line.

## Resultant displacement formula

The resultant displacement formula is used when the distance from point of reference is used to specify the initial and final position of the object. Despite the fact that distance and displacement are not the same things, displacement problems will tell you how many “foot” or “meters” an object has traveled. Problems would also mention along which direction (North, east, south, west) our object is traveling.

The resultant displacement formula is given by relation
$d=\sqrt{x^2+y^2}$
where, $d$ is displacement.
$x$ is the object’s initial direction of motion and
$y$ is the second direction in which the object is moving.