Motion Do Now Make a ramp with the

Motion

Do Now: Make a ramp with the yellow bin and the piece of wood. Race two objects down the ramp. Which object has more speed? How can you tell?

SWBAT: explain when an object is in motion and how it is in motion relative to a reference point • Vocabulary: • Motion: an object is in motion when its distance from another object is changing •

Do Now 1. How do you know an object is in motion? 2. Which is faster, a runner who moves 100 meters in 10 seconds, or a runner who moves 100 meters in 20 seconds? How do you know?

Reference point • Sometimes it is not so easy to tell if something is moving – we are always moving

Relative Motion • Am I moving? Compared to the tree? Compared to the windshield?

Reference point • reference point: a reference point is a place or object used for comparison to determine if something is moving • Measuring motion always depends on a reference point

Speed • Speed = distance in one unit of time • Speed = distance / time Speed does not have to be FAST!

Speed Do NOW; Using what you learned yesterday write 2 sentences about this graph. 6 5 Distance in m 4 3 2 1 0 Category 1 Time in sec

Velocity • velocity = the speed and the direction of an object’s movement

Velocity • We use meters to measure distance • • mm: 1, 000 mm = 1 m Cm: 100 cm = 1 m Km: 1000 m = 1 km We use meters per second, or m/s, to measure speed and velocity. _ ______

Exit ticket • Use the words speed, distance, and time. Tell me about the relationship of speed to distance if the time stays the same. • As distance traveled increases, speed ______. • As speed increases, distance traveled ______.

Velocity • Calculate an object’s speed and velocity using SI units • Velocity = distance / time in sec

Acceleration • SWBAT describe what happens to the motion of an object as it accelerates, • SWBAT define and identify acceleration

Acceleration • Acceleration: rate of velocity change in either speed or direction. • Acceleration can be increasing speed, decreasing speed or change of direction. • • Acceleration= (final v – initial v) / time

Acceleration – change in speed or direction

Acceleration? Yes or NO?

Acceleration? Yes or NO?

Do Now: Roll the marble to your elbow buddy. List 2 things you can change about the motion of a rolling marble.

Forces • Force: a push or a pull • Includes STRENGTH and DIRECTION

Net Forces • Net force: overall force on an object after all forces are added together, • If Net force is not zero it is unbalanced force • An unbalanced force acting on an object will change an object’s motion

Balanced Forces • BALANCED FORCES: equal forces acting in opposite directions • A balanced force will not change an object’s direction

SWBAT: State Newton’s first law of motion, and define inertia • Inertia: the tendency of an object to resist change in motion • Newton’s first law of motion states that an object in motion will remain in motion and an object at rest will remain at rest unless acted upon by an unbalanced force

http: //teachertech. rice. edu/Participants/louviere/Newton/

Newton’s Second Law of Motion • Force depends on mass and acceleration Force = Mass x Acceleration F= M x A Force is measured in Newtons (N)

FORCE • Force depends on both mass and acceleration • Force is measured in Newtons • Force = Mass x Acceleration • F= M x A

DO NOW • When you go sledding, what force makes you slide down the hill? • What force stops you? • Would you go as far if there wasn’t any snow on the hill? • Why?

Friction and Gravity • Friction and gravity are two forces that affect nearly all motion • What determines the strength of the force of friction?

What determines the strength of the force of friction? • The type of the two surfaces • The force which they are pressed together (how hard they rub) • Heat is produced as a result of friction – some mechanical energy turns into thermal energy http: //videos. howstuffworks. com/discovery/2 8985 -coming-home-from-space-shuttlereentry-video. htm

The 2 persons are pushing each other on ice. (so no outside force). The grandma has twice the mass (inertia) than the little girl. Are they going to feel the same force ? according to what law ? Are they going to move as fast ? which one is going to move faster ?

Newton’s 3 rd law • For every action, there is an equal and opposite reaction • If an object exerts a force on a 2 nd object the 2 nd object exerts and equal and opposite force on the first object

Do Now: Explain the cartoon

Newton’s 3 rd Law of Motion • For every action there is an EQUAL and OPPOSITE reaction

How does this show Newton’s 3 rd law