Here's why:
* Speed: A force can cause an object to accelerate (increase speed) or decelerate (decrease speed).
* Direction: A force can change an object's direction of motion, even if its speed remains constant. This is why you need to steer a car to turn, or push a ball sideways to change its trajectory.
* Both: Many forces cause both changes in speed and direction. Think about throwing a ball. You apply a force that sends it moving forward (increasing its speed), and you also aim your throw to give it a specific direction.
In summary: Forces are the "push" or "pull" that can alter an object's state of motion. This includes changes in how fast it's going (speed) and which way it's going (direction).
