Here's why:

* Contact Force: A contact force requires direct physical contact between two objects to exert an influence.

* Water Resistance: When an object moves through water, the water molecules physically interact with the object's surface, creating a resistance force that opposes the motion.

Example: When you swim, you feel the water pushing against your body, slowing you down. This is due to the contact force of water resistance.

Let me know if you have any other questions!