Q7. A car travels 50 meters east in 15 seconds. What is the car's average velocity? Q8. A motorcycle starts from a standstill. In 15 seconds it reaches a velocity of 20 m/s. What is the motorcycle's average acceleration? Q9. During the U.S. trials for the 2004 Summer Olympics, Michael Phelps broke his own world record in the 400 meter individual medley when he was clocked at 4 minutes and 08.41 seconds. What was his average velocity and his average speed? Give your answer in SI units. Q10. Sitting in the passenger seat you observe that the drive of the car needs only 3 seconds to come from a speed of 35 mph on the entrance ramp to the interstate to a speed of 70 mph on the interstate. What is the car's acceleration? How much distance does the car cover during those 3 seconds? Find out what the values of acceleration for some sports cars are and give these values here. Include how these values compare to the acceleration that you calculated. Q11. Polar bears are strong swimmers and can swim as long as 10 hours without rest. If a polar bear swims with an average speed of 2.6 m/s, what is the total distance it can swim in 10.0 hours? Give your answer in km. Q12. How long does it take a baseball to travel the 18.4 m from the pitcher's mound to home plate when thrown at a speed of 34.5 m/s? Q13. An airplane starts at rest at the end of a runway. If it reaches a speed of 80 m/s in 18 s, what is the plane's acceleration? Q14. If a race car at rest (not moving) accelerates to a speed of 120 m/s in 32 s. What is the car's acceleration? Q15. You drop a rock from the top of a tall cliff. After 1.50 seconds the velocity of the rock is measured to be 14.7 m/s in a downward direction. What is the rock's acceleration? What would it's instantaneous velocity be in another 0.50 s? Q16. A motorcycle starts with velocity of 10 m/s then accelerates for 40 m/s² for 2.0 seconds. What is it's final velocity? Q17. How long does it take the minute arm/hand on a wall clock or wrist watch to make one revolution? Measure the length of that minute arm/hand on the wall clock or wrist watch and show all work as you calculate the speed of the tip of the minute arm. Q18. A projectile accelerates from 0 to 280 m/s in 0.5 seconds. What is it's acceleration? Q19. How long will it take an object with an average velocity of 45 m/s to travel 825 m?