Presentation on theme: "Force, Motion, and Energy"— Presentation transcript:
1 Force, Motion, and Energy Newton’s LawsSpeed, Velocity, AccelerationGravity
2 Motion Motion occurs when an object changes its position. Three Types of Motion:Relative MotionYou v. solar systemDistanceHow far something movesDisplacementDifference between the end and the startNOT total distance
3 Speed Distance traveled per unit of time Speed = distance time Example…You ran 2 km in 10 minutes.What was your speed?
4 VelocitySpeed (a change in position over a period of time), but in a specificdirection.Example: The cars at the TexasMotor Speedway drove a lap.They go 120 mph for 60 sec W,120 mph for 30 sec S,120 mph for 60 sec E, and 120 mph for 30 sec N. They had a direction which means they also had velocity.
5 AccelerationAcceleration occurs when an object changes its speed, direction, or both.Acceleration = change in velocitychange in timeWhen an object changes its direction or speed, it is accelerating.
6 Force A force is a push or a pull that one object applies to another. A force can also cause an object’s motion to change.EX) SportsBalanced forces are equalin size and opposite in direction.
7 InertiaInertia is the tendency of an object to resist any change in its motion.Objects with more mass havemore inertia.
8 Newton’s First LawAn object in motion tends to stay in motion and an object at rest tends to stay at rest until acted on by an outside force.
9 Force, Mass, Acceleration For any object, the greater the force, the greater the acceleration.The acceleration of any object depends on its mass AND the forceexerted on that object.KEY CONCEPT: Force, mass,and acceleration are connected.
10 Newton’s 2nd Law of Motion Describes how force, mass, and acceleration are connected.REMEMBER:Net force = total forces actingon an object.States that the net force acting onan object causes the object toaccelerate in the direction of the net force.
11 Newton’s 2nd Law of Motion Acceleration of an object is determined by the size of the net force acting on the object and the mass of the object.So, the relationship betweenacceleration, net force, andmass can be defined as:F = ma
12 Friction If we give a skateboard a push, what happens? But according to Newton’s 1st Law, what SHOULD happen?REMEMBER:When an object slowsdown, its velocity changes; if itsvelocity changes, it is accelerating.If an object is accelerating, a netforce must be acting upon it.
13 FrictionThe force acting on the skateboard is friction. Friction is the force that opposes motion between 2 surfaces that are touchingeach other.The amount of friction between2 surfaces depends on 2 factors:The kinds of surfaces.The force pressing the surfaces together.
14 Static Friction What does “static” mean? Applied force is equal to the friction between the two surfaces.
15 Sliding FrictionApplied force is greater than the friction between the two surfaces.
16 Rolling FrictionThe friction between a rolling object and the surface it rolls on.Rolling friction is usually much less than static or sliding friction.That is why it is easier to pull a load in a wagon rather than dragging it along the ground.
17 Friction Foldable Term Definition/ Example Picture Friction Static FrictionSliding FrictionRolling Friction
18 Newton’s Third LawFor every action, there is an equal and opposite reaction.Examples:TrampolineRocket Propulsion