Physic forces concept details for Junior science Olympiad competition

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Welcome to our exploration of forces! A force is simply a push or a pull that acts on an object. Forces can change how objects move, making them speed up, slow down, or change direction. Forces can also change an object's shape, like compressing a spring. Every force has both magnitude, which tells us how strong it is, and direction, which tells us which way it acts. We measure forces in units called Newtons. Now let's explore the different types of forces we encounter every day. Gravitational force, also called weight, is the force that pulls objects toward Earth's center. Friction is the force that opposes motion when two surfaces rub against each other. The normal force is the support force that a surface exerts perpendicular to an object resting on it. Applied force is any force directly applied by a person or another object. Understanding these basic force types helps us analyze how objects interact in the world around us. Newton's First Law, also known as the Law of Inertia, tells us that objects resist changes in their motion. If an object is at rest, it will stay at rest unless a force acts on it. If an object is moving at a constant speed in a straight line, it will continue moving that way forever unless an unbalanced force changes its motion. This property of matter to resist changes in motion is called inertia. The more massive an object is, the more inertia it has, making it harder to start, stop, or change its direction.