The mud particles fly off the wheels of a vehicle moving on a wet road due to the phenomenon known as "water adhesion". Water molecules have a strong cohesive force, which means they tend to stick together. When a vehicle moves through a wet road, the water on the road sticks to the wheels due to the adhesive forces. As the wheels rotate, the water is dragged along with them and eventually flung off due to centrifugal force. This process causes the mud particles that are present in the water to fly off the wheels as well.
In addition to water adhesion, the speed of the vehicle also plays a role in determining the extent to which mud particles are thrown off the wheels. The faster the vehicle moves, the greater the centrifugal force and the more water and mud particles are flung off.
To reduce the amount of mud and water that is thrown off the wheels of a vehicle, some vehicles are equipped with mudguards or splash guards. These devices help to block the water and mud from being thrown up into the air.
