3) What information about the motion of an object can be determined from a Velocity Vs. Time graph?

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1 Name Date Unit 3: Velocity-Time Graphs and Acceleration Review Section 1: Know the definitions and/or graphical representations of the following vocabulary words. 1) Describe the motion of an object if it is moving at a constant velocity. 2) What are the three ways an object can change its velocity? 3) What information about the motion of an object can be determined from a Velocity Vs. Time graph? 4) What basic information about an objects motion cannot be determined from a Velocity Vs. Time Graph? 5) What is meant by uniform acceleration? 6) An object has a negative velocity but a positive acceleration. What does this mean about the motion of the object? 7) An object has a negative velocity and a negative acceleration. What does this mean about the motion of the object? 8) If you had the below velocity vs. time graph, describe how would you find displacement and average acceleration during the time interval t=3 s to 7 s?

2 Velocity (m/s) Section 2: Work through each of the following problems. 1) Use the velocity-time graph to answer the questions below a) Find the average accelerations and the displacements for the following time intervals from the velocity vs. time graph: Average Acceleration Displacement in Time Interval in m/s 2 meters to 6 seconds 6 to 15 seconds Velocity - Time Graph to 24 seconds 24 to 33 seconds Time (s) b) Use the graph to determine the objects instantaneous acceleration at 6.75 s. 2) A ball is rolled to the right across a table. The motion diagram is shown below. d =.1 m t =.125 s d 1 =.263 m t 1 =.25 s d 2 =.488 m t 2 =.375 s d 3 =.763 m t 3 =.5 s d 4 = 1.75 m t 4 =.625 s d 5 = 1.9 m t 5 =.75 s d 6 = 1.1 m t 6 =.875 s a) What is the direction of the velocity and acceleration of the ball? b) Is the ball speeding up, slowing down or maintaining a constant velocity? How do you know?

3 3) Use the velocity-time graph to answer the questions below. a) Name two specific clock readings at which the object turns around. g) Find the average acceleration from 2 s to 9 s? b) Name the two time intervals in which the object is traveling in the positive direction. h) Find the average acceleration from 6 s to 1 s? c) Name the one time interval in which the object is traveling in the negative direction. d) Name a time interval in which the object is moving in the positive direction but it has a negative acceleration. e) During which time interval(s) is the object only moving at a constant non-zero speed? f) During which time interval(s) does the object only have displacements to the left (-)? i) Find the average acceleration from 1 s to 4 s? j) Find the displacement of the object from t= s to 3 s. k) Find the displacement of the object from t= 3 s to 8 s. l) Find the displacement of the object from t= 8 s to 1 s. m) Find the displacement of the object from t= s to 1 s. 4) A Toyota Corolla has an initial velocity of m/s. If the Corolla has a constant acceleration of m/s 2, what is its velocity after 5.62 s? (Use a = v v and solve for final velocity, v.) t

4 5) A ball is tossed into the air. What is its acceleration at the highest point in its trajectory? 6) Sketch a velocity vs. time graph of a basketball that is thrown straight up in the air and falls down to the ground. 7) A car is moving north on the freeway, the driver presses on the brakes. What is the direction of the acceleration of the car? Graph matching- supply the missing description or the missing graph. Each situation represents one dimensional motion. Velocity versus Time Histories 9) Written Interpretations 1) An object, initally at rest, increases its velocity uniformly in the positive direction then slows to a stop and speeds up uniformaly in the negative direction. 11) 12) An object stars out moving in the positive direction and maintains a constant velocity.

5 Position (m) Velocity (m/s) Consider the following P-T and V-T graphs of an object moving along a straight level path. Both graphs are of the same object in motion. Position-Time Graph Velocity-Time Graph Time(s) Time (s) 13) Which graph would you use to find the initial position of the object? 19) Find the average acceleration from 12 s to 37 s? Explain your choice. 2) Find the average velocity from 16 s to 32 s? 14) What is the initial position of the object? 21) Find the average velocity from 16 s to 36 s? 15) Describe the motion of the object using the graphs above. 22) Find the instantaneous acceleration at 8 s. 16) Find the displacement of the object from s to 16 s using the P-T graph. (Show your work.) 23) Find the instantaneous acceleration at 34 s. 17) Find the displacement of the object from s to 16 s using the V-T graph. (Show your work.) 24) Find the instantaneous velocity at 8 s. 18) Find the average acceleration from s to 33 s? 25) Find the instantaneous velocity at 34 s.