We looked at problems involving impulse and change in momentum. There were three forms of impulse that were all equivalent, you choose which one based on the information you have. Change in momentum, the sum of the forces multiplied by time or the impulse written with the letter J.
The problems we did involved finding the change in momentum.
In a different situation, you might know what force is applied and for how long.
The direction can be very important in calculations and can signify opposite directions.