2.  To describe motion in terms of displacement, time, acceleration and velocity.  To interpret graphs of position vs. time.  To apply kinematic equations to calculate distance, time or velocity under conditions of constant acceleration.  To relate the motion of free falling objects to motion with constant acceleration.

5. Did YOU know? The branch of physics concerned with motion and forces is called mechanics. The subset of mechanics that describes motion without regard to its causes is called kinematics.

6. In teams search for different plane schedules and calculate the average velocities of a plane flying the same route in opposite directions. Hypothesize about why there is a difference. Share your findings with the rest of the group.

7. Your team of experts has been assigned with investigating the recent accident of a train in Spain. You have the following information:  A video of the accident http://www.youtube.com/watch?v=5HgijA7zz-c  The train was a RENFE Class 130 Your mission to prove if the rumor that the train was going at twice the allowed speed (80km/h) on that part of the track are true. Post your findings on the Socrative exit ticket.

8. Read and reread the problem carefully before trying to solve it. Decide what objects or objects you are going to study and for what time interval. You can often choose the initial time to be t=0. Draw a diagram or picture of the situation. Usually we choose the x axis to the right as positive. Write down the known or given quantities the what you want to know. Think about which principles of physics apply in the problem. Consider which equations relate to the quantities involved. Carry out the calculation. Think carefully about the result obtained: Is it reasonable? Does it make sense according to your own intuition and experience? Keep track of the units. If the units do not balance, a mistake has no doubt been made.

9. The position of a runner as a function of time is plotted as moving along the x axis of a coordinate system. During a 3.00 second time interval, the runner’s position changes from x1= 50.00m. To x2= 30.5m. What is the runner’s average velocity? Solution: -6.50 m/s How far can a cyclist travel in 2.5h along a straight road if her average velocity is 18 km/h? Solution: 45 km.

10. If you are driving 110km/h along a straight road and you look to the side for 2.0 seconds, how far do you travel during the inattentive period? Solution: 61.11 m. A bowling ball traveling with constant speed hits the pins at the end of the bowling lane 16.5m long. The bowler hears the sound of the ball hitting the pins 2.50 seconds after the ball is released from his hands. What is the speed of the ball? Consider speed of sound as 340 m/s Solution: 6.73 m/s

11. An object whose velocity is changing is said to be accelerating. Acceleration specifies how rapidly the velocity of an object is changing. Average acceleration the is expressed as:

16. A car slows down uniformly from a speed of 21 m/s to rest in 6 seconds. How far did it travel in that time? Solution: 63m.

18. Galileo formulated the laws that govern the motion of objects in free fall.

19. A fast flash photograph shows two objects of different weight dropped at the same time and falling with the same acceleration.

20. If Batman drops from a 10.5 m height. Find the following information: a)Batman’s total flight time. b)Batman’s velocity when he hits the speeding car. c)Batman’s velocity at mid flight.

21. Supose a ball is thrown from a tower 70m high with an initial velocity of 3m/s. a) What will be the position after 1s, 2s? b) What would be the speed after 1s and 2s? Solution: 7.90m, 25.6m 12.8 m/s, 22.6m/s A person throws a ball upward into the air with an initial velocity of 15m/s. Calculate a) how high it goes, b) how long the ball is in the air before it comes back to his hand, c) how much time it takes for the ball to reach the maximum height, and d) the velocity of the ball when it returns to the thrower’s hand. Solution: 11.5m 3.06s1.53s -15m/s

23. The time t is considered the independent variable and is measured along the horizontal axis. The position x, the dependent variable and is measured along the vertical axis. The slope of the x vs. t graph is equal to the velocity.

24. Similarly, the slope at any point of an v vs. t graph equals the acceleration at that moment.

25. Giancoli, Douglas C. Physics Sixth Edition. USA Pearson 2005 Serway, Raymond A. Essentials of College Physics. USA Thomson 2007 http://www.youtube.com/watch?v=_Kv-U5tjNCY http://www.youtube.com/watch?v=3BETTsLOgQI&feature=related