Reminder: We are covering this because the average score on this benchmark was 40%! SC.6.P.13.3 Investigate and describe that an unbalanced force acting on an object changes its speed, or direction of motion, or both. SC.6.P.12.1 Measure and graph distance versus time for an object moving at a constant speed. Interpret this relationship.

Benchmark Break ↓ Balanced Forces Unbalanced Forces Day One Agenda Benchmark Break ↓ Balanced Forces Unbalanced Forces Big Ole Box Example Airplane Example Formative Checkpoint

Benchmark Break ↓ SC.6.P.13.3 Investigate and describe that an unbalanced force acting on an object changes its speed, or direction of motion, or both. REWRITE: KNOW: Balanced forces result in an object at rest. Unbalanced forces require the calculation of net force AND the direction of motion. DO: Describe the different forces acting on an object. Calculate and predict the net force and/or direction in scenarios.

Balanced Forces Objects at rest (not moving) are a result of balanced forces. Gravity pulls you down. The floor or your chair pushes upward. Newton’s Rule: Objects at rest will stay at rest until a new force acts on it.

Unbalanced Forces When forces on an object are Unbalanced, it results in motion. Applying force changes an object’s speed and/or direction.

Big Ole Box Example Gravity and the floor’s force are balanced. Which direction will the box move? With how much force will it be moving? GRAVITY YOU Push with 50 N of force Big Ole Box of Books To the right… Friction opposes motion with 10 N FLOOR 40 N of force

Airplane Example What causes drag? Friction between the plane and air. What would cause the airplane to descend towards the ground? If the lift is less than the weight (unbalanced)

Objects Stay at Rest Until a New Force Acts Upon It!

FORMATIVE CHECKPOINT DAY #1 What happens when the forces applied to an object at rest produce a net force of zero? The object will move at constant speed. The object will have positive acceleration. The object will have negative acceleration. The object will not move at all.

Benchmark Break ↓ Formative Checkpoint Positive/Negative Acceleration Day Two Agenda Benchmark Break ↓ Positive/Negative Acceleration Speed=Distance/Time Interpreting D vs T Graphs Step-By-Step Video Formative Checkpoint

Benchmark Break ↓ SC.6.P.12.1 Measure and graph distance versus time for an object moving at a constant speed. Interpret this relationship. REWRITE: KNOW: How to interpret a D vs T graph to describe the motion of object(s). DO: Interpret a distance vs time graph by explaining where + or – acceleration is taking place, or when an object is holding still.

Positive and Negative Acceleration Positive Acceleration: When an object increases its speed. (speeds up) Negative Acceleration: When an object decreases its speed. (slows down) Negative Acceleration 25 km/h 50 km/h

Positive and Negative Acceleration Origin: Where you start. Moving away from origin. Returning to Origin

Speed= Distance/Time (like miles per hour in your car) What is the speed from point A→B? 0.6 km/hr What is the speed from point C→D? 2.25 km/hr

Interpreting D vs T Graphs What is happening between B→C and D→E? The object is holding still! What is the speed from E→F? 2 km/h Headed back to the origin.

Interpreting D vs T Graphs http://www.youtube.com/watch?v=pNbsvnUdqCo

Day Two Formative Assessment Cheyenne is drawing a graph that shows four different objects and the distance each object travels in 5 seconds. Which line on the graph shows the object that is traveling with the fastest constant speed?