Do Now for Wednesday! Draw a balanced and an unbalanced force. Illustrate the net force in each drawing. Consider the Following! WHAT TYPE OF FORCES ARE NECESSARY IN ORDER FOR AN OBJECT TO MOVE? THERE ARE TWO POSSIBLE ANSWERS. Forces = Pushes & Pulls! We know that the strength of a force is measured in SI units called NewtonsAfter Sir Isaac Newton. 1 Newton is equal to about 102 grams ( pounds). Sir Isaac Newton Net Force is the sum or difference of the forces on an object. Net force = 300N Green Team Wins! What is a NON-ZERO FORCE? Same as an unbalanced force! Non-zero = Unbalanced = Movement! What is a ZERO FORCE? Same as a balanced force! Zero force = Balanced = NO Movement Balanced? So what is WORK?? Work is done when an object is moved in the direction in which a force is applied to it. Is There Work Without Motion? NOPE! No Work Here! Carrying your backpack to school might seem like work - but its not! ^^^FORCE^^^FORCE DIRECTION The force must be in the direction the object moves!!! Pushing, dragging or pulling your backpack = work! FORMULA FOR WORK! Work = Force X Distance (Newtons)(Meters) Work is calculated as the amount of force applied to an object times the distance the object moves. The term JOULE is used to describe a unit of work. (Joule) FYI A 500N runner in the Empire State Buildings Run-Up-Race creates 160,000 joules of work while climbing the 1,576 steps. Enough work to lift an elephant over 3 meters! What is Power? FORMULA FOR POWER! Power = WorkOR Power = Force X Distance Time Time Power is described in Joules/Second units called WATTS. One joule of work done in one second = one watt of power. A watt is a very small unit! Power is often measured in larger units such as Kilowatts (Kw) or Horsepower (hp). 1 Kilowatt = 1,000 watts 1 Horsepower = 746 watts The average car has 110 150 hp. The average semi-truck has hp A drag race car can have over 5,000 hp The average horse has 22.5 hp. Try some Equations!