1. A car accelerating: When you press the gas pedal in a car, the engine provides a force that pushes the car forward. This force increases the car's speed, changing its velocity.
2. A ball being thrown: When you throw a ball, your hand exerts a force on it, causing it to accelerate from rest. The ball gains both speed and a direction of motion, resulting in a change in velocity.
3. A ball rolling to a stop: As a ball rolls across the floor, friction between the ball and the floor creates a force that opposes the ball's motion. This force gradually slows the ball down, decreasing its velocity until it eventually comes to a stop.
