Mrs. Wright NEWTON’s FIRST LAW of MOTION. FORCE  A force is a push or a pull on an object.  All forces have a STRENGTH (measured in NEWTONS) and a direction.

Presentation on theme: "Mrs. Wright NEWTON’s FIRST LAW of MOTION. FORCE  A force is a push or a pull on an object.  All forces have a STRENGTH (measured in NEWTONS) and a direction."— Presentation transcript:

Mrs. Wright NEWTON’s FIRST LAW of MOTION

FORCE  A force is a push or a pull on an object.  All forces have a STRENGTH (measured in NEWTONS) and a direction.  For Example:  It takes about 45N to lift the average cat

Sir Isaac Newton  In the late 1600’s Sir Isaac Newton developed 3 laws to describe how objects move and react in our universe to forces such as  Gravity  Friction  Inertia  In order to understand these laws, you must first understand INERTIA.

INERTIA~ AKA: Law of inertia InertiaInertia - the tendency of an object to resist being moved, or if the object is moving, to resist a change in speed or direction until an outside force acts on the object OR The tendency of an object to resist any changes in motion. These pumpkins will not move unless acted on by an unbalanced force.

Newton’s 1 st law of motion  An object at rest remains at rest, and an object in motion remains in motion at the constant speed and in a straight line unless acted on by an unbalanced force.

Objects At Rest: An Object at rest is…. A.) not moving B.) moving

Objects At Rest: An Object at rest is…. A.) not moving B.) moving

Objects At Rest:  Objects at rest, such as a chair, desk, book, etc…, will not move by itself unless a force is placed on it. AHHHH… GHOST!!!

At rest (not moving) Unbalanced force (moving)

Objects In Motion  Moving objects will continue to move forever in the same velocity unless an unbalanced force acts on them.

QUESTION… Scenario… You are riding a bus to school. When you finished your candy bar, you stand up to walk to the front of the bus. SUDDENLY, a mouse runs in front of the bus and the bus driver slams on his brakes (he loves mice)……. What will happen to you? why?

Friction & Newton’s First Law Newton says, “an object in motion will stay in motion forever…unless acted on by a unbalanced force. If you push your desk, what will happen?

Will the desk move FOREVER? What makes it stop?

FRICTION!!!!!  Friction- a force that opposes motion between two surfaces that are in contact.

Mass & Inertia The smaller the mass, the less the inertia Small/light objects are easier to move, or stop from moving. Large/heavy objects are harder to move, or stop from moving.

Wile E. Coyote Watch CLIP and write down 3 examples of when Newton’s first law of motion was demonstrated. After the clip, go back and briefly explain WHY it demonstrates Newton’s 1 st law. CLIP

VOCABULARY ~  Speed: The distance traveled by an object in a certain amount of time  Acceleration: The CHANGE in speed of an object  Law: A scientific theory that has been proven consistently true. Usually laws help explain how our universe works.

Download ppt "Mrs. Wright NEWTON’s FIRST LAW of MOTION. FORCE  A force is a push or a pull on an object.  All forces have a STRENGTH (measured in NEWTONS) and a direction."

Similar presentations