What are the answers for all questions
far on CW 1.2 Average speed and Average velocity Thursday, August 8. 2019 1:48 PM Average Speed and Average velocity ( SHOW ALL WORK IN YOUR NOTEBOOK) 1. Carl Lewis set a world record for the 100.0-m run with a time of 9.86 s. If, after reaching the finish line, Mr. Lewis walked directly back to his starting point in 90.9 s, what is his average speed for the total time ? 2. A hiker travels south along a straight path for 1.5 h with an average speed of 0.75 km/h, then continues south for 2.5 h with an average speed of 0.90 km/h. What is the hiker's distance traveled for the total trip? What is the hiker's average speed for the trip ? 3. A motorcyclist travels 350 km from home on the first day of a trip. The second day he travels at 75 km/h for 8.0 hours. How far is he from home at the end of the second day? 4. A businesswoman on a trip flies a total of 23,000 km. The first day she traveled 4000 km, the second day 11,000 km, and on the final day she was on a plane that could travel at an average speed of 570 km/h. How long was she on the plane the final day? 5. A person travels from one city to another by car with different constant speeds between pairs of cities. She drives for 30.0 min at 80.0 km/h, the next 25 km at 90 km/h and the last 45.0 min at 40.0 km/h and spends 12.0 min eating lunch and buying gas. A) Determine the total distance between the initial and final cities along this route. B) Determine the average speed of the trip. 6. It is now 10:43 a.m., and the bell rings at 10:44 a.m. Susan must get from one side of the school to the other by hurrying down three different hallways. She runs down the first hallway, a distance of 35.0 m, at a speed of 3.50 m/s. The second hallway is filled with students, and she covers its 48.0 m length at an average speed of 1.20 m/s. The final hallway is empty, and Suzette sprints its 60.0 m length at a speed of 5.00 m/s. Does Susan make it to class on time or does she have to go to the front office to get tardy pass? 7. A turtle takes 3.5 minutes to walk 20 m toward the south along a deserted highway. A truck driver stops and picks up the turtle. The driver takes the turtle to a town 1.1 km to the north with an average speed of 10 m/s. What is the magnitude of the average velocity of the turtle for its entire journey? 8. A black mumba, the world's most poisonous snake sees a prey and begins slithering out toward it with a velocity of 18.0km/h. After 2.30s, the mumba realizes that its prey can move faster than it can. The snake then turns around and slowly returns to its hideout in 12.0 s. Calculate i. the mumba's average velocity for the complete trip. ii. the mumba's average speed for the complete trip. Challenge Problems 9. You are driving home from school steadily at 65mph for 130 miles. It then begins to rain and you slow to 55mph. You arrive home after driving 3 hours and 20 minutes. How far is Unit1. Motion in 1D Page 1
