Enter the initial momentum, final momentum, and total time into the calculator to determine the drop force.

## Drop Force Formula

The following equation is used to calculate the Drop Force.

Fd = (Mi-Mf) / t
• Where Fd is the drop force (N)
• Mi is the initial momentum (kg-m/s)
• Mf is the final momentum (kg-m/s)
• t is the change in time (s)

To calculate a drop force, subtract the final momentum from the initial momentum, then divide by the time.

It’s important to note that in the case of an object that bounces off a surface, the final momentum will be negative since it changed direction.

## What is a Drop Force?

Definition:

Drop force is a term primarily used in material testing where the impact force of a falling object on a target is measured.

At its core, drop force is a measurement of the impact that an object will experience as it falls onto a surface

## How to Calculate Drop Force?

Example Problem:

The following example outlines the steps and information needed to calculate the Drop Force.

First, determine the initial momentum. In this example, the initial momentum of a ball is 500 kg*m/s.

Next, determine the final momentum. After the ball bounces off a surface, the final momentum is -200 kg*m/s.

Next, determine the change in time. The change in time during the bounce is measured to be 5 seconds.

Finally, calculate the drop force using the formula above:

Fd = (Mi-Mf) / t

Fd = (500-(-200)) / 5

Fd = 140 N