Force & MotionDate:

7.P.1 Understand motion, the effects of forces on motion and the graphical representations

of motion.

7.P.1.1 Explain how the motion of an object can be described by its position, direction of motion,

and speed with respect to some other object.

7.P.1.2 Explain the effects of balanced and unbalanced forces acting on an object (including friction,

gravity and magnets).

7.P.1.3 Illustrate the motion of an object using a graph to show a change in position over a period of

time.

7.P.1.4 Interpret distance versus time graphs for constant speed and variable motion.

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Location, location, locationHow can you describe the location of an object?•________________ describes the location of an object.

•_______________ using _________ objects or locations often are used to describe position.

•A _________________ is a location to which you compare other locations.

MOVE It!What is motion?•___________ is a change in position over time.

•Even when motion is not observed directly, __________ points and end points can indicate motion has occurred.

How is distance measured?•___________ can be measured as a straight line between __ positions.

•Distance can also be measured as the _________ length of a certain path between two positions.

•The standard _____ of length for distance is the __________ (m).

What is speed?•____________ is a measure of how far something moves in a given amount of time.

•Speed measures how __________ or slowly an object changes its position.

•______ objects move _________ than slower objects in the ______ amount of time.

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What is average speed?•____________ speed is a way to calculate the speed of an object that may not always be moving at a constant speed.

•Average speed describes the speed over a ___________ of time rather than at any exact moment in time.

Speed It Up!How is average speed calculated?•Speed can be ____________ by dividing the distance an object travels by the time it takes to cover that distance.

•speed = ________/________

•s = d/t

•If ___ objects travel the same distance, the object that takes _______ time has the ___________ speed.

•An object with a __________ speed travels _________ in the same time than an object with a _________ speed travels.

•The standard ______ for speed is ________ per ___________ (m/s).

Fast GraphsHow is constant speed graphed?•Distance-time _________ are used to ______ the ___________ an object travels _______ time.

•The _____________ of an object away from a reference point is plotted on the ___-axis. ________ is plotted on the ___-axis.

•Objects moving at a ____________ speed make a __________ line on the graph.

•The _______, or steepness, of the line is _________ to the __________ speed of the object.

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•Average speed can be ______________ by dividing the change in distance by the change in time for that time interval.

•__________ = change in y/change in x

How are changing speeds graphed?•On a distance-line graph, a ___________ in the slope of a line ____________ a change in speed.

•If the line gets _____________, the object’s speed has ______________.

•If the line gets _____ steep, the object has ___________ down.

•A _______ line indicates _______ speed.

Follow DirectionsWhat is velocity?•A ___________ is a quantity that has both size and direction.

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•_____________ is speed in a specific direction.

•Objects can have the ________ speed but ____________ velocities because of their _____________ of travel.

•_____________ velocity ____________ on the distance from the starting point to the final point.

•Average velocity can be 0 km/h if you travel at a certain speed to one point and then travel back to the starting point.

A Tour de ForcesWhat is a force, and how does it act on an object?•In science, a ________ is a push or a pull.

•____ forces are ___________. This means they have _______ a size and a direction.

•The ______ used to express force is the ____________ (N).

•Forces ____________ always cause motion.

•Forces can ______ on objects that are in ____________ with each other. Such a force is called a contact force.

•_____________ is an example of a contact force between two surfaces that are touching.

•Car ______ rely on friction to keep a moving car from sliding off a road. Cars may slide on icy roads because ice lowers the force of friction on the tires.

•Forces can also act on objects that are at a _______________.

•____________ is a force that _______ objects toward Earth.

•____________ forces can also act at a distance. Magnetic force can be a _____, as when a magnet holds paper to a metal refrigerator door, or a _______, as when like poles of two magnets push each other apart.

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In the BalanceWhat happens when multiple forces act on an object?•The ________________ is the combination of all the forces acting on an object.

•When forces act in the _________ direction, they are _________ to determine net force.

•When forces act in _____________ directions, the smaller force is _______________ from the larger force.

•A net force of _______ means the forces are _____________ and will not cause a change in motion.

•________________ forces produce a _____________ in an object’s motion. The object could change __________, _____________, or both. This change in motion is called an acceleration.

•_____________________ is always in the direction of the net force.

It’s the LawWhat is Newton’s First Law of Motion?•Sir Isaac Newton described ___ laws of motion that explain the relationship between force and motion.

•Newton’s ____ law describes the __________ of an object that has a net force of __ N acting on it.

•The law states: An object at rest _______ at rest, and an object in motion stays in motion at the same speed and direction, _________ it experiences an unbalanced force.•Newton’s first law is also called the law of __________.

•____________ is the tendency of all objects to resist any change in motion.

•The law of inertia ____________ why a chair will not slide across the floor unless a force pushes the chair, and why a golf ball will not leave the tee until a force pushes it off.

What is Newton’s Second Law of Motion?

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•Newton’s ___ law states: The _____________ of an object depends on the _____ of the object and the ____________ of force applied.

•force = _________ × _______________ (F = ma)

Newton’s Second Law and You•Have you ever been on a roller coaster? Did you feel like you were going to float out of your seat when you went over a big hill?

•When a roller ____________ is going up a hill, there are ___ important forces acting on you: the force of ___________ and the __________ force exerted by the roller coaster seat.

•Once the roller coaster starts down the other side of the hill, it ______________ downward, and your seat does not support your full weight.

•The airplane’s path looks like a roller coaster hill. As the plane accelerates downward, the passengers lose contact with the plane and fall toward Earth. This condition is called _______________.

It’s the LawWhat is Newton’s Third Law of Motion?•Newton’s ___ law states: Whenever ___ object _________ a force on a __________ object, the second object exerts an ________ and ______________ force on the first.

•In other words, all forces act in ____________.•___________ and reaction forces are present even when there is ___ motion.

•Even though action and reaction forces are _________ in size, their effects are _____________.

•An object can have _____________ forces acting on it at once. When this happens, each force is part of a force pair.

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