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Daily Agenda. Ms. DeSalvo November 15, 2013. CPS Bell Ringer 11/15/13 Activity: Vectors. When we are drawing the force diagrams, what do the arrows around the object represent?. CPS (Period 6,8) November 15, 2013. Last Class (See me for missed work) Force Diagrams Diagrams. Today
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Daily Agenda Ms. DeSalvo November 15, 2013
CPS Bell Ringer 11/15/13Activity: Vectors When we are drawing the force diagrams, what do the arrows around the object represent?
CPS (Period 6,8)November 15, 2013 Last Class (See me for missed work) • Force Diagrams • Diagrams Today • Force Vectors • Force Vector HW Due Monday.
Vectors!!! • Represented by an: • Size of Arrow: Magnitude “how much” • Direction of Arrow: direction of property • Ex: Direction of velocity
Adding Vectors • If vectors are in the same direction: • Line the arrows up and add magnitude 6 m/s + 2 m/s = 8 m/s right
Subtracting Vectors • If vectors are in the opposite direction: • stack the arrows and subtract (right – left) 6 m/s - 2 m/s = 4 m/s right
Practice Vector A Vector B Vector C 6 m/s 1 m/s 4 m/s • Vector A + Vector B • Vector A – Vector C • Vector B – Vector C
Force: An action exerted on an object (a push or a pull) in order to change the state of rest or motion of an object. Measured in Newtons (N) Net Force: • Combination of all the forces acting on an object. (add them up)
Balanced Forces • If all of the pushes and pulls are even on an object, then the object “keeps on doing what it was doing” • Tug-o-war • Two teams that are evenly matched play tug-o-war • NOTHING HAPPENS
Unbalanced Forces • Unbalanced forces cause objects to change velocities • Tug-o-war • Two teams that are unevenly matched play tug-o-war • One team will win
Unbalanced Force • What happens when an object has an unbalanced force acted upon it? • Unbalanced forces cause acceleration!
If the forces are… • Equal – • Nothing happens • Ex: A book sitting on a shelf • Fg = 25 N • FN = 25 N • Unequal – • The object changes what it is doing • Ex: • FA = 25 N right • FA = 100 N left
Practice Problem • What is the net force acting on a 5 kg ball in free fall?