9 III. ApplicationWorksheet goes here once graded!
10 IV. ConnectionToday your boss informed you that you have a meeting tomorrow morning at 8:00 am. Cool…BUT, it’s in Waco. WACO!! That’s 168 miles away. You don’t know how long it will take to get there, but the speed limit is 70 mph. You don’t want to get a ticket, so what time will you have to leave??
11 Hmmmm…Speed = 70mphDistance = 168 miT = D/TTime = 168/70 = 2.4 hours** (2.4 is not 2 hours and 40 minutes!!!)***What time do I leave?
12 2.4 is almost 2 ½ hours..4 = 4/10Make a proportion!4/10 = x/60X = 24It is actually 2 hours and 24 minutes. I would need to leave at 5:36!
13 V. EndingDescribe why it’s important to calculate speed (write 4-5 sentences).
15 FocusGrab your notebook and complete the quizTurn in once complete
16 Notes on Velocity and Acceleration Set up your foldable
17 VELOCITY Speed (D/T) in a given DIRECTION. Example: 30 mph heading East
18 VELOCITY EXAMPLEWhat would your velocity be if you traveled 1 km east in 0.5 h?V = DTV = 1 km0.5 hV = 2 km/h EastDirectionEast
19 ACCELERATION The rate of change in velocity. Can be speeding up, slowing down or changing directions
20 CALCULATING ACCELERATION Acceleration = Final Velocity – Initial VelocityTime
21 ACCELERATION EXAMPLEExample: Riding your skateboard, it takes you 12 s to accelerate from 2 m/s to 8 m/s. What is your acceleration?A = 8 m/s – 2 m/s12 sA = 6 m/sA = 0.5 m/s2
22 Example: Riding your skateboard, it takes you 12 s to accelerate from 8 m/s to 2 m/s. What is your acceleration?A = 2 m/s – 8 m/s12 sA = - 6 m/sA = m/s2 (slowing down)
23 III. ApplicationWorksheet goes here once graded!
24 IV. Connection1. Find the velocity in m/hr of a runner who runs exactly 100m north in exactly 2 hours.2. What would his acceleration be if he started at that velocity, but ended with a velocity of 75m/hr?
25 V = D/T D= 100m T= 2 hours V = 100/2 = 50 m/hr north Acceleration: 75-50225/2 = 12.5 m/s squared
26 V. Ending Fill in your Speed tab from your notes Compare and Contrast speed, velocity and acceleration (write 4-5 sentences).
27 FORCE FORCES CAUSE ACCELERATION! Push or pull Affects motion: Set the object in motionStop its motionChange the speed and direction of its motionFORCES CAUSE ACCELERATION!
28 FORCE FACTS Measured in Newtons (N) Act in pairs Act in a particular direction
29 Push or Pull? Changing speed, direction or both?
30 TWO THINGS AFFECTING MOTION How strong the forces areThe direction of the forces
31 NET FORCEWhen more than one force acts on an object, the forces combine to form a net force.Same direction – ADDOpposite directions - SUBTRACT
32 BALANCED FORCES Opposite in direction & equal in size NO change in movement2000 N2000 N2000 N – 2000 N = 0 N
33 UNBALANCED FORCES Not always opposite and not equal in size Causes movement5000 NGRAVITY1000 NRESISTANCEAIR5000 N – 1000 N = 4000 N
34 EXAMPLE The forces shown above are PUSHING / PULLING forces. The forces above are WORKING TOGETHER / OPPOSITE FORCES?The forces are BALANCED/ UNBALANCED.The forces DO / DO NOT balance.The stronger force is pulling to the RIGHT / LEFT.The weaker force is pulling to the RIGHT / LEFT.Motion is to the RIGHT / LEFT.100 N200 N
35 TYPES OF FORCES Buoyant Force Magnetic Force Electrical Force Gravitational ForceElastic ForceCentripetal ForceFrictional Force
36 FRICTION A force opposing (going against) motion Brings an object to rest
37 FOUR TYPES OF FRICTIONSliding Friction – 2 solid surfaces sliding over each other *** Opposes motion the most!Rolling Friction – Object rolling over a surfaceFluid Friction – Object moves through a fluid (liquid or a gas)Static Friction – The force of 2 surfaces in contact but does not cause movement