2.  Simple Machine – a machine that does work with only one movement of that machine.  Ideal Mechanical Advantage – the term that is used to describe the amount of force that is utilized internally by some sort of mechanical device; the ideal mechanical advantage (IMA) for any machine can be calculated by dividing the input distance by the output distance; IMA = length of input arm (L in )/length of output arm (L out )

3.  Lever – an arm that pivots (or turns) against a fulcrum (or point).  3 Orders  http://www.enchantedlearning.com/physics/machines/Leve rs.shtml http://www.enchantedlearning.com/physics/machines/Leve rs.shtml

4.  Design Catapults and make a drawing using graphing paper  Specifications Sheet  Average Speed of Projectile  Force of Projectile

5.  John uses a lever to lift a weight of 5 N. The input distance (where the input force is applied) is 50 cm. The output distance (where the output force is applied) is 5 cm. What is the ideal mechanical advantage of the lever?  IMA = input distance/output distance

6.  10 Popsicle sticks  1 plastic spoon  10 rubber bands  12 inches of tape

7.  Obtain the mass of the marshmallow  Set up your catapult 2 meters from the target  Record the time it takes your marshmallow to reach the target  3 trials

8.  With how many Newtons of force did the Marshmallow hit the target?  F = ma  Newton’s Second Law – the acceleration of an object is directly proportional to the unbalanced force acting on it and inversely proportional to the object’s mass. The direction of the acceleration is the same as the direction of the unbalanced force.

9.  Mass – the amount of matter in an object; unit: kg  Weight – the vertical, downward force exerted on a mass as a result of gravity; unit: N

10.  We need acceleration!  Acceleration – the change in velocity per unit time; a = Δ v/ Δ t; unit: m/s/s  GRAPH YOUR RESULTS

11.  We need the change in velocity!  Speed – the distance traveled divided by the time elapsed; speed is a scalar quantity, it has no direction v = Δ d/ Δ t; unit: m/s  Velocity – the speed in a given direction; displacement divided by the time interval; v = Δ d/ Δ t; unit: m/s  Use the time that it took your marshmallow to travel from the catapult to the target  GRAPH YOUR RESULTS

12.  Vector – a quantity that has both magnitude (size/amount) and direction  Scalar – a quantity that has magnitude (size/amount) but no direction

13.  Projectile – an object traveling through the air or other medium with no power source of its own  Shape of the path of the projectile?  Parabola – a plane curve; the shape of a projectile  Gravitational force – 9.8 m/s/s  In what direction would it travel if there was no gravity?  Newton’s First Law – in the absence of an unbalanced force, an object at rest remains at rest, and an object in motion remains in motion with constant speed in a straight-line path  Inertia – the natural tendency of an object to remain at rest or to remain moving with constant speed in a straight line

14.  With how many Newtons of force did the Marshmallow hit the target?  F = ma  With how many Newtons of force did the target strike back?  Newton’s Third Law – forces come in pairs; the force of object A on object B is equal in strength and opposite in direction to the force of oject B on object A

15.  SMART BOARD

16. 1.Simple Machine 2.Lever 3.Vector 4.Scalar 5.Parabola 6.Mass 7.Acceleration 8.Speed 9.Velocity 10.Projectile 11.Newton’s First Law 12.Newton’s Second Law 13.Newton’s Third Law 14.Inertia

17.  John Deere was hunting with his new crossbow. His crossbow was equipped to shoot bolts, or arrows, that have a mass of 0.50 kg. He spotted a turkey that was about 35.00 m away and quickly set up and shot down the turkey. He estimated that the bolt reached the turkey in about 2.00 seconds. With how much force did the bolt hit the turkey?  HINTS  F = ma  a = Δ v/ Δ t  v = Δ d/ Δ t