Laws of Motion

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    Here are some resources to start thinking about forces and motion all around you. Remember, I always say there are a lot of laws and rules in the real world. Well, in science, there are far less. Before you dive into the resources on the next page (you will find a link at the bottom of this page) and throughout your learning in the physical sciences, think about Newton's 3 Laws of Motion. They rule over all the learning you will do:

    • 1st law, also called the Law of Inertia:

      • You learned this as a baby.

      • Objects will only move if a force (Forces from humans, wind, earthquake, etc.) causes the object to move.

      • If no force is applied, the object remains "at rest" or not moving. If forces are balanced, the object also does not move (see picture below).

    Balanced forces

    • 2nd law, also know as Force = mass x acceleration:

      • You learned as a baby, but you keep learning this law every day of your life as you encounter new things.

      • Objects that have greater MASS, like a bowling ball, need more FORCE to move than a soccer ball. The bowling ball can be said to be heavier, denser, or having more MASS than the soccer ball.

      • Objects that are moving faster (ACCERERATING) will demonstrate more FORCE. If I through a bowling ball to you from the second floor of a building, you will experience more FORCE than if I handed it to you.

      • Objects with greater FORCE have more MASS, or ACCELERATION, or both MASS and ACCELERATION. (Think of you a bumping into a parked car vs. a moving car bumping into you. Why might both hurt you?)

     2nd law b                         2nd law c

    • 3rd law states that when an object exerts force on anther object, the second object exerts a equal force and opposite force on the first object.

      • This law can be most difficult to see, but it is still happening all the time. The problem is that forces cannot always be seen (think of gravity).

      • This law really needs some visuals, so CLICK HERE for more information.