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Warm-Up:. Warm-Up: 1. Give an example of something with speed . 2. Give an example of something with velocity. Warm-Up: 1. What would be the velocity of a bird that flies 10 miles South in 2 hours? 2. What is the acceleration of a car that goes from a stop to 100km/h in 6 seconds?.
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Warm-Up: 1. Give an example of something with speed.2. Give an example of something with velocity.
Warm-Up: 1. What would be the velocity of a bird that flies 10 miles South in 2 hours?2. What is the acceleration of a car that goes from a stop to 100km/h in 6 seconds?
Warm-Up: 1. What is the difference between speed and velocity?2. What is acceleration?
Acceleration=final velocity – starting velocitytime it takes to change velocity
Motion ______ –distance over time _______ – speed and direction __________ – the rate at which velocity changes
Motion Calculate the total velocity for each of the passengers. 0km/h west 5km/h east 4km/h west Airplane: 800km/h west
Motion • QUICK REVIEW • What information must you know in order to calculate speed? • What is the error in the following statement: • The velocity of the car is 55km/hr.
Motion D S T Cover the one you’re looking for.
Motion Application: Speed Calculations A pitcher threw a baseball 150m in 2 seconds. How fast was the ball going? A girl can run 50m/s. How long will it take her to run 1000m? You drove 80km/h for 3 hours. How far did you go?
Mini quiz! Application: Speed Calculations A car drove 120 miles in 3 hours. How fast was it going? A sprinter can run 60 m/s. How long will it take her to run 600m? You drove 50 mi/h for 8 hours. How far did you go?
Motion Everybody Writes! In your own words, describe the motion shown by each graph. (Hint: Be sure to look at the labels on the x and y axis.) Graph 1
Motion Everybody Writes! In your own words, describe the motion shown by each graph. (Hint: Be sure to look at the labels on the x and y axis.) Graph 2
Motion Everybody Writes! In your own words, describe the motion shown by each graph. (Hint: Be sure to look at the labels on the x and y axis.) Graph 3
Motion Everybody Writes! In your own words, describe the motion shown by each graph. (Hint: Be sure to look at the labels on the x and y axis.) Graph 4
Motion Application: Speed Calculations How fast would you have to drive to go from Atlanta to New York (900 miles) in 10 hours? A red car drove 150km at a speed of 50km/h. A blue car drove 300km at a speed of 75km/h. Which car reached its destination first?
Motion Application: Speed Calculations A plane flies 100 km east for 10 minutes, then 200 km for 10 minutes, and then 50 km for 5 minutes. What is the plane's average velocity? Did the plane accelerate?
Motion Application: Speed Calculations You will drive to a town that is 100km away. Half the trip you will be able to drive 100km/h (on the highway) and half the trip you will drive 50km/h (going through small towns). How long will it take you to get there? Show your work!
Motion Distance-Time Graphs ---- Car 1 ---- Car 2 Graph showing the speed of a car • Which car drove at a constant speed? • Which car accelerated? • Which car is faster? How do you know? • Which car drove farther after 1 hour? After 6 hours? Distance (km) Time (h)
Motion Distance-Time Graphs Calculate the average speed at each point: _________ _________ _________ _________ Did the car accelerate or stay at a constant speed? How do you know? D C B A
Motion • Distance-Time Graphs • The following graph shows the distance Kyle traveled on his bicycle trip and the amount of time it took him to travel that distance. During which 5-minute interval did Kyle achieve the greatest average speed? What may have happened between t = 10 and t = 15 minutes?
Motion Quiz What two things must you know to calculate speed? What is wrong with the following statement: The velocity of a car is 100km/h Turning left, slowing down, and speeding up are all examples of __________. How fast would you have to drive to go from Atlanta to New York (900 miles) in 9 hours? A red car drove 400km at a speed of 50km/h. A blue car drove 600km at a speed of 75km/h. Which car reached its destination first? YOU MUST SHOW YOUR WORK FOR CREDIT!
Motion Quiz • Which car drove the farthest after 1 hour? • How far did each car drive in 7 hours? • Red Car _____ • Blue Car: ____ ---- Blue Car ---- Red Car Graph showing the speed of cars Which car accelerated? Which car stayed at a constant speed? What best explains the motion of the red car between t=1 and t=4? Distance (km) Time (h)
Practice:A golf ball is hit north off a tee and 2 seconds later, it is traveling 300 m/s
Practice:A car is traveling south at 20 mph and after 10 seconds is traveling 60 mph
Target: (#21)Read about the Great Pyramids on pg. 186.1. What are the pyramids made from?2. How did the Egyptians lift the blocks?
Notes: Work & MachinesWork occurs when a force causes an object to move in the direction of the force
Force & Motion must be in the same direction for work to occur
Work = Force x Distance1. How much work is done when you apply a force of 10 N to lift a bag 1 meter?2. How much work is done when a force of 200 N is used to move a car 20 meters?
Power is the rate at which work is doneThe unit for power is the watt.Power =Work Time
Power =Work Time3. If you do 60 J of work in 10 seconds, what is your power?
Warm-Up:1. How much work (in joules) does a person do if they apply a 100N force a distance of 10 meters?2. How much power does a horse generate if it does 600 joules of work in 60 seconds?
A machine is a device that makes work easier by changing the size or direction of the force
The work you do on a machine is called the work input (input force).
The work done by the machine is called work out put (output force).
Machines don’t reduce the work, they change the size or direction of the force
The force-distance trade-off: force or distance can increase, but not together
Target1. If you exert 10 N of force on an object and the object does not move, did you do any work?2. What units are used for power?
Target (#24)1. The work done on a machine is called the __________ __________.2. The work done by the machine is called the ___________ _________.