____/ 25 Name___________________ Date_____________Per____ Motion Reading Guide 1. Speed = ________________ / ________________. (1) 2. km / hr is read as kilometers _______ hour and means to divide the _________________ by the_______________ interval. (3) 3. Average speed = __________________________ / time interval. (1) 4. What is the average speed of a cheetah that sprints 100 m in 4 seconds? (Show work, include units.) (2) 5. Distance = _____________________________ x ______________________. (1) 6. A car moved at an average speed of 60 km/h for 1 hour. How far did it go? (Show work, include units.) (2) 7. Speed is relative. How fast is the classroom traveling relative to the sun? (1) 8. Define velocity. (1) 9. If a car travels in a circle at a constant rate of speed, does it change velocity? Why or why not? (2) 10. What are three ways that we can change the velocity of something? (3) 11. Define acceleration. (2) 12. If a car goes from rest to 90 km/h in 10 seconds, what is its acceleration? (Show work, include units.) (2) 13. If a car increases its velocity from 60 km/h to 65 km/h in 2 seconds, what is its acceleration? (Show work, include units.) (2) 14. If a bicycle goes from rest to 5 km/h in 2 seconds, what is its acceleration? (Show work, include units.) (2) Motion Reading Guide KEY 1. Speed = DISTANCE / TIME. (1) 2. km / hr is read as kilometers PER hour and means to divide the KILOMETERS by the TIME interval. (3) 3. Average speed = TOTAL DISTANCE COVERED / time interval. (1) 4. What is the average speed of a cheetah that sprints 100 m in 4 seconds? (Show work, include units.) (2) 110 m / 4 s = 25 m / s 5. Distance =AVERAGE SPEED / TIME INTERVAL. (1) 6. A car moved at an average speed of 60 km/h for 1 hour. How far did it go? (Show work, include units.) (2)(60 KM / HR)(1 HR) = 60 KM 7. Speed is relative. How fast is the classroom traveling relative to the sun? (1) 30 KM / SEC 8. Define velocity. (1) v = SPEED + DIRECTION 9. If a car travels in a circle at a constant rate of speed, does it change velocity? Why or why not? (2) YES, CHANGES DIRECTION 10. What are three ways that we can change the velocity of something? (3) CHANGE SPEED, CHANGE DIRECTION, CHANGE BOTH 11. Define acceleration. (2) RATE OF CHANGE IN VELOCITY 12. If a car goes from rest to 90 km/h in 10 seconds, what is its acceleration? (Show work, include units.) (2) a = ∆v / ∆ t = v 2 – v 1 = 90 km/hr – 0 km/hr = 90 km/ hr / sec t2–t1 10 s – 0 s 13. If a car increases its velocity from 60 km/h to 65 km/h in 2 seconds, what is its acceleration? (Show work, include units.) (2) a = ∆v / ∆ t = v 2 – v 1 = 65 km /hr – 60 km /hr = 2.5 km / hr / sec t2–t1 2 sec 14. If a bicycle goes from rest to 5 km/h in 2 seconds, what is its acceleration? (Show work, include units.) (2) 5 km / hr – 0 km / hr = 5 km / hr = 2.5 km / hr / sec 2 sec – 0 sec 2 sec